A- (3) prefix meaning "not," from Gk a-, an- "not," from pie base *ne "not" (see un-)

impudent --- c.1386, from L. impudens (gen. impudentis), from in- "not" + pudens (gen. pudentis), prp. of pudere "to cause shame."

impugn --- 1362, from O.Fr. impugner, from L. impugnare "to assault, to attack," from in- "upon" + pugnare "to fight" (see pugnacious).

impulse --- 1432 (implied in impulsion) "an act of impelling, a thrust, push," from L. impulsus "a push against, pressure, shock," also "incitement, instigation," pp. of impellere (see impel). Meaning "stimulus in the mind arising from some state or feeling" first recorded 1647. Impulsive (1604) originally was in ref. to medicines that reduce swelling or tumors; sense of "rash" first recorded 1847.

impunity --- 1532, from L. impunitatem (nom. impunitas) "freedom from punishment, omission of punishment," from impunis "unpunished, without punishment," from in- "not" + poena "punishment."

impute --- c.1375, from O.Fr. imputer, from L. imputare "to reckon, account, charge, ascribe," from in- "upon" + putare "reckon, clear up, trim, prune, settle."

in --- O.E. in "in," inne "within," from P.Gmc. *in (cf. O.Fris, Du., Ger., Goth. in, O.N. i), from PIE *en-/*n (cf. Gk. en, L. in, O.Ir. in, Welsh yn-, O.C.S. on-). Sense of "holding power" (the in party) first recorded 1605; that of "exclusive" (the in-crowd, an in-joke) is from 1907; that of "stylish, fashionable" (the in thing) is from 1960. The noun sense of "influence, access" (have an in with) first recorded 1929 in Amer.Eng. The suffix -in attached to a verb originated 1960 with sit-in, probably infl. by sit-down strike, used first of protests, extended c.1965 to any gathering. In-and-out "copulation" is attested from 1620. To be in like Flynn is 1940s slang, said to be U.S. military, perhaps from alleged sexual exploits of Hollywood actor Errol Flynn.

in- (1) --- prefix meaning "not, opposite of, without" (also im-/il-/ir- by assimilation of -n- with following consonant), from L. in- "not," cognate with Gk. an-, O.E. un- (see un- (1)).

in- (2) --- prefix meaning "into, in, on, upon" (also im-; il-; ir- by assimilation of -n- with following consonant), from L. in- "in" (see in). In O.Fr. this often became en-, which was usually respelled in Eng. to conform with L., but not always, which accounts for pairs like enquire/inquire. There was a native form, which in W.Saxon usually appeared as on- (cf. O.E. onliehtan "to enlighten"), and some verbs survived into M.E. (cf. inwrite "to inscribe"), but all now seem to be extinct.

in loco parentis --- 1710, from L., lit. "in the place of a parent."

in media res --- 1786, from L., lit. "in the midst of things."

inadvertently --- 1678, lit. "inattentively," hence "unintentionally;" ult. from inadvertence (1568), from Scholastic L. inadvertentia, from in- "not" + advertentia, from L. advertere "to direct one's attention to," lit. "to turn toward" (see advertise).

inamorata --- female lover, 1651, from It. innamorata, fem. of innamorato, pp. of innamorare "to fall in love," from in "in" + amore "love."

inane --- silly, empty-headed, 1819, earlier "empty" (1662), a back-formation of inanity "emptiness, hollowness" (1603), later "silliness" (1753), from Fr. inanité, from L. inanitatem "emptiness," from inanis "empty, void, worthless, useless." Inanition is attested from c.1400.

inarticulate --- 1603, "not clear or intelligible" (of speech), from L.L. inarticulatus "indistinct," from in- "not" + articulatus, pp. of articulare (see articulation).

inasmuch --- contraction of in as much, first attested c.1300 as in als mikel, a Northern form. First contracted to in asmuch, then, beginning 14c. and especially since 17c., to one word.

inauguration --- 1569, from Fr. inauguration "installation, consecration," from L. inaugurationem (nom. inauguratio) "consecration, installment under good omens," from inaugurare "take omens from the flight of birds, consecrate or install when such omens are favorable," from in- "on, in" + augurare "to act as an augur, predict" (see augur).

inborn --- O.E. inboren "native to a place," from in- "within" + boren "brought forth" (see born). Of qualities in a person, 1513.

Inc. --- U.S. abbreviation of Incorporated in company names (equivalent of British Ltd.), first attested 1906.

Inca --- 1594, from Sp. (1526), from Quechea, lit. "lord, king." Technically, only of the high Inca, but it was used widely for "man of royal blood."

incalculable --- 1795, from in- "not" + calculable (see calculation).

incandescent --- 1794, from L. incandescentem (nom. incandescens), prp. of incandescere "become warm, glow, kindle," from in- "within" + candescere "begin to glow, become white," inceptive of candere "to glow, to shine" (see candle).

incantation --- 1390, from O.Fr. incantation (13c.), from L. incantationem (nom. incantatio) "art of enchanting," from incantus, pp. of incantare "bewitch, charm," lit. "sing spells" (see enchantment).

incapable --- 1601, from in- "not " + capable.

incapacity --- 1611, from M.L. incapacitas, from L.L. incapax (gen. incapacis) "incapable," from in- "not" + L. capax "capable," lit. "able to hold much," from capere "to take" (see capable). Often used 17c. as a legal term referring to inability to take, receive, or deal with in some way.

incarceration --- 1536, from O.Fr. incarceration, from M.L. incarcerationem (nom. incarceratio), from incarceratus, pp. of incarcerare "imprison," from in- "in" + carcer "prison, an enclosed space," of uncertain origin. The verb incarcerate is first attested 1560.

incarnadine (v.) --- 1591 (adj.) "flesh-colored," from Fr. incarnadine, from It. incarnadino "flesh-color," from L.L. incarnatio (see incarnation). The verb properly would mean "to make flesh colored," but the modern meaning "make red," and the entire survival of the verb, is traceable to "Macbeth" II ii. (1605).

incarnation --- 1297, "embodiment of God in the person of Christ," from O.Fr. incarnation (12c.), from L.L. incarnationem (nom. incarnatio), "act of being made flesh" (used by Church writers esp. of God in Christ), from L. incarnatus, pp. of incarnare "to make flesh," from in- "in" + caro (gen. carnis) "flesh."

incendiary --- person who sets malicious fires (n.), 1606; "concerning malicious fires" (adj.), 1611, from L. incendiarius (n.), from incendium "conflagration," from incendere "set on fire," from in- "in" + *candere "to set alight, cause to glow," related to candere "to shine" (see candle). Fig. sense of "enflaming passions" (adj.) is from 1614. Military use, of bombs, shells, etc., attested from 1871. The obsolete verb incend is attested from 1502.

incense (n.) --- c.1290, from O.Fr. encens "sweet-smelling substance," from L.L. incensum (nom. incensus) "burnt incense," lit. "something burnt," neut. pp. of L. incendere "set on fire," from in- "in" + *candere "to set alight" (see incendiary).

incense (v.) --- make angry, 1435, from M.Fr. incenser, from L. incensare, freq. of L. incendere "set on fire" (see incense (n.)). A figurative use of the word used literally in incense (n.).

incentive --- 1432, from L.L. incentivum, noun use of neut. L. adj. incentivus "setting the tune" (in L.L. "inciting"), from stem of incinere "strike up," from in- "in, into" + canere "sing" (see chant). Sense infl. by association with incendere "to kindle." The adj. use, in ref. to a system of rewards meant to encourage harder work, first attested 1943 in jargon of the U.S. war economy; as a noun, in this sense, from 1948.

inception --- c.1483, from L. inceptionem (nom. inceptio), from inceptus, pp. of incipere "begin, take in hand," from in- "in, on" + cipere comb. form of capere "take, seize" (see capable).

incessant --- 1461 (implied in incessantly), from O.Fr. incessant (1358), from L.L. incessantem (nom. incessans) "unceasing," from L. in- "not" + cessantem (nom. cessans), prp. of cessare "cease."

incest --- c.1225, "the crime of sexual intercourse between near kindred," from L. incestum "unchastity," also specifically "sex between close relatives," noun use of neut. adj. incestus "unchaste, impure," from in- "not" + castus "pure" (see caste). In early use also in ref. to sexual relations or marriage with one under a vow of chastity (sometimes distinguished as spiritual incest).

inch (1) --- linear measure, one-twelfth of a foot, late O.E. ynce, M.E. unche (current spelling c.1300), from L. uncia "a twelfth part," from root of unus "one;" an early borrowing from L., not found in any other Gmc. language. Transf. and fig. sense of "a very small amount" is attested from c.1350. The verb meaning "move little by little" is first recorded 1599, from the noun. Inchworm first recorded 1861. For phrase give him an inch ... see ell.

inch (2) --- small Scottish island, c.1425, from Gael. innis (gen. innse) "island, land by a river."

inchoate --- 1534, from L. inchoatus, pp. of inchoare, alteration of incohare "to begin," originally "to hitch up," from in- "on" + cohum "strap fastened to the oxen's yoke."

incident --- 1412, "something which occurs casually in connection with something else," from L. incidentem (nom. incidens), prp. of incidere "happen, befall," from in- "on" + -cidere, comb. form of cadere "to fall" (see case (1)). Sense of "an occurrence viewed as a separate circumstance" is from 1462. Meaning "event that might trigger a crisis or political unrest" first attested 1913. Incidental "casual, occasional" first recorded in Milton (1644). Conversational use of incidentally for "by the way" first attested 1925.

incinerate --- 1555, from M.L. incineratus "reduce to ashes," pp. of incinerare, from L. in- "into" + cinis (gen. cineris) "ashes." Incinerator first recorded 1883, originally in the Amer.Eng. terminology of cremation; meaning "device for waste disposal by burning" is from 1889.

incipient --- 1669, from L. incipientem (nom. incipiens), prp. of incipere "begin, take up," from in- "on" + -cipere, comb. form of capere "to take" (see capable).

incipit --- opening word of a Latin book or manuscript, from L., lit. "(here) begins," third person sing. pres. indic. of incipere (see incipient).

incision --- 1392, from O.Fr. incision (13c.), from L. incisionem (nom. incisio) "a cutting into," noun of action from incidere "to cut in," from from in- "into" + -cidere, comb. form of caedere "to cut" (see concise). Incisive (1597), from M.L. incisivus originally was lit., "cutting with a sharp edge;" fig. sense of "mentally acute" first recorded 1850 as a borrowing from Fr.

incisor --- cutting tooth, 1672, from M.L. incisor, lit. "that which cuts into," from L. incisus, pp. of incidere (see incision).

incite --- 1447, from M.Fr. enciter (14c.), from L. incitare "to put into rapid motion, urge, encourage, stimulate," from in- "on" + citare "move, excite" (see cite).

inclement --- 1559 (implied in inclemency), from L. inclementem (nom. inclemens) "harsh, unmerciful," from in- "not" + clementem "mild, placid." "Limitation to weather is curious" [Weekley].

incline (v.) --- c.1305, "to bend or bow toward," from O.Fr. encliner, from L. inclinare "to cause to lean," from in- "in" + clinare "to bend," from PIE *klei-n-, suffixed form of *klei "to lean" (see lean (v.)). Metaphoric sense of "have a mental disposition toward" is c.1430 in Eng. (but existed in classical L.). The noun meaning "slant, slope" is attested from 1846.

include --- 1402, from L. includere "to shut in, enclose, insert," from in- "in" + claudere "to shut" (see close (v.)). The alleged Sam Goldwyn-ism, "Include me out," is attested from 1937.

incognito --- 1649, from It. incognito "unknown," especially in connection with traveling, from L. incognitus "unknown," from in- "not" + cognitus, pp. of cognoscere "to get to know" (see cognizance). Fem. form incognita was maintained through 19c. by those scrupulous about Latin.

incoherence --- 1611, formed from in- "not" + coherence on model of It. incoerenza (see coherence).

income --- c.1300, "entrance, arrival," lit. "what enters," perhaps a noun use of the late O.E. verb incuman "come in," from in (adv.) + cuman "to come" (see come). Meaning "money made through business or labor" first recorded 1601. Income tax is from 1799, first introduced in Britain as a war tax, re-introduced 1842; authorized on a national level in U.S. in 1913. Incoming was originally of game approaching the hunter.

incommensurable --- 1557, from M.L. incommensurabilis, from in- "not" + L.L. commensurabilis, from L. com- "with" + mensurabilis "measurable," from mensurare "to measure."

incommunicable --- 1568, "not communicative," from in- "not" + communicable (see communication). Sense of "not able to be communicated" first recorded 1577.

incommunicado --- 1844, Amer.Eng., from Sp. incomunicado, pp. of incomunicar "deprive of communication," from in- "not" + comunicar "communicate," from L. communicare "to share, impart," from communis (see common).

incomparable --- 1412, from O.Fr. incomparable (12c.), from L. incomparabilis, from in- "not" + comparabilis "comparable" (see comparison).

incompatible --- 1563, from M.L. incompatibilis, from in- "not" + compatibilis (see compatible). Originally of benefices, "incapable of being held together;" sense of "mutually intolerant" is from 1592.

incompetent --- 1611, "insufficient," from Fr. incompetent, from L.L. incompetentem, from in- "not" + L. competentem (see competent). Sense of "lacking qualification or ability" first recorded 1635.

incomplete --- c.1380, from L. incompletus, from in- "not" + completus (see complete).

incomprehensible --- c.1340, from L. incomprehensibilis, from in- "not" + comprehensibilis (see comprehend).

inconceivable --- 1631, from in- "not" + conceivable (see conceive).

incongruous --- 1611, from L. incongruus, from in- "not" + congruus (see congruent).

inconsequent --- 1579, "not following as a logical conclusion," from L. inconsequentem (nom. inconsequens) "not logically connected," from in- "not" + consequens, pp. of consequi "to follow" (see consequence). Inconsequential "not worth noticing" first attested 1782.

inconsiderate --- c.1460, "done thoughtlessly," lit. "not properly considered," from L. inconsideratus "unadvised, thoughtless," from in- "not" + consideratus (see consider).

inconsistent --- 1646, "not agreeing in substance or form," from in- "not" + consistent (q.v.).

inconspicuous --- 1624, "invisible," from L.L. inconspicuus, from in- "not" + L. conspicuus (see conspicuous). Sense of "not readily seen or noticed" first recorded 1828.

inconstant --- 1402, "fickle, not steadfast," from M.Fr. inconstant, from L. inconstantem, from in- "not" + constantem (see constant).

incontinent --- c.1380, "wanting in self restraint," from O.Fr. incontinent, from L. incontinentem, from in- "not" + continent (see continent). Originally chiefly of sexual appetites; sense of "unable to control bowels or bladder" first attested 1828.

inconvenient --- 1398, "not agreeing or constant," from Fr. inconvenient (13c.), from L. inconvenientem, from in- "not" + convenientem (see convenient). Sense of "troublesome, awkward" first recorded 1651.

incorporate --- 1398, "to put (something) into the body or substance of (something else)," from L.L. incorporatus, pp. of incorporare "unite into one body," from L. in- "into" + corpus (gen. corporis) "body" (see corporeal). The legal sense first recorded in Rolls of Parliament, 1461.

incorporeal --- 1532, from L. incorporeus "without body," from in- "not" + corpus (gen. corporis) "body" (see corporal).

incorrect --- 1432, "uncorrected," from L. incorrectus, from in- "not" + correctus (see correct). Sense of "not in good style" is from 1672; that of "factually wrong, erroneous, inaccurate" is from 1828.

incorrigible --- 1340, from O.Fr. incorrigible (1334), or from L. incorrigibilis "not to be corrected," from in- "not" + corrigere "to correct."

increase (v.) --- c.1315, from Anglo-Fr. encress-, from O.Fr. encreiss-, prp. stem of encreistre, from L. increscere "to increase," from in- "in" + crescere "to grow" (see crescent). L. spelling restored 15c.

incredible --- 1412, from L. incredibilis "that cannot be believed," from in- "not" + credibilis "worthy of belief" (see credit). Incredulity "disbelieving frame of mind" first attested 1430; incredulous "unbelieving" is from 1579.

increment --- c.1425, "act or process of increasing," from L. incrementum "growth, increase," from stem of increscere "to grow in or upon" (see increase). Meaning "amount of increase" first attested 1631.

incriminate --- 1730, from M.L. incriminatus, pp. of incriminare "to incriminate," from in- "not" + criminare "to accuse of a crime," from crimen (gen. criminis) "crime" (see crime).

incroyable --- 1796, from Fr., lit. "incredible," from in- "not" + croire "to believe," from L. credere. Name for the French fop or dandy of the period of the Directory (1795-99). Said to be so called from their extravagant dress or from a favorite expression among them ("C'est vraiment incroyable").

incubation --- 1614, "brooding," from L. incubationem (nom. incubatio) "a laying upon eggs," from incubatus, pp. of incubare "to hatch," lit. "to lie on," from in- "on" + cubare "to lie." The lit. sense of "sitting on eggs to hatch them" first recorded in Eng. 1646. The verb incubate is first attested 1721. Incubator "apparatus for hatching eggs by artificial heat" first attested 1857.

incubus --- c.1205, from L.L. (Augustine), from L. incubo "nightmare, one who lies down on (the sleeper)," from incubare "to lie upon" (see incubate). Plural is incubi. In the Middle Ages, their existence was recognized by law.

inculcate --- 1550, from L. inculcatus, pp. of inculcare "force upon, stamp in," from in- "in" + calcare "to tread, press in," from calx "heel."

inculpate --- 1799, "to accuse, bring charges against," from M.L. inculpatus, pp. of inculpare "to reproach, blame, censure," from L. in- "in" + culpare "to blame," from culpa "fault." But inculpable (1491) means "not culpable, free from blame," from L. in- "not" + culpare.

incumbent (n.) --- c.1410, from M.L. incumbentem (nom. incumbens) "holder of a church position," from prp. of incumbere "to obtain or possess," from L. incumbere "recline on, apply oneself to," from in- "on" + -combere "lie down," related to cubare "lie." Extended to holders of any office from 1672. As an adj., first recorded 1567, in relation to duties or obligations; the lit., physical sense is rare in Eng. and first attested 1624.

incur --- c.1430, from Anglo-Fr. encurir, from L. incurrere "run into or against," from in- "upon" + currere "to run" (see current).

incurable --- 1340, from O.Fr. incurable (13c.), from L. incurabilis, from in- "not" + curabilis "curable" (see cure).

incursion --- hostile attack, 1432, from L. incursionem (nom. incursio) "a running against," from incurrere (see incur).

indebted --- c.1386, "owing money," from O.Fr. endette, pp. of endetter "to involve in debt," from en- "in" + dette "debt" (see debt). Fig. sense of "under obligation for favors or services" first attested 1561.

indecent --- 1563, "unbecoming, in bad taste," from L. indecentem, from in- "not" + decentem (see decent). Sense of "offending against propriety" is from 1613. Indecent assault (1861) originally covered sexual assaults other than rape or intended rape, but by 1934 it was being used as a euphemism for "rape."

indecision --- 1703, from Fr. indecision (1611), from in- "not" + decision (see decision). Indecisive first attested 1726.

indecorous --- 1682, from L. indecorus, from in- "not" + decorus (see decorum).

indeed --- c.1330, in dede "in fact, in truth," from O.E. dæd (see deed). Written as two words till c.1600. As an interjection, 1598; as an expression of surprise or disgust, 1834. Emphatic form in yes (or no) indeedy attested from 1856, Amer.Eng.

indefatigable --- 1586 (implied in indefatigably), from Fr. indefatigable (15c.), from L. indefatigabilis "that cannot be wearied," from in- "not" + defatigare "to tire out," from de- "utterly, down, away" + fatigare "to weary" (see fatigue).

indefensible --- 1529, from in- "not" + defensible (see defense).

indefinable --- 1810, from in- "not" + definable (see define).

indefinite --- 1530, from L. indefinitus, from in- "not" + definitus (see define).

indelible --- 1529, from L. indelebilis "indelible, imperishable," from in- "not" + delebilis "able to be destroyed," from delere "destroy, blot out" (see delete).

indelicate --- 1742, "offensive to propriety," from in- "not" + delicate (q.v.).

indemnity --- 1444, from M.Fr. indemnité (1367), from L.L. indemnitatem (nom. indemnitas) "security for damage," from L. indemnis "unhurt, undamaged," from in- "not" + damnum "damage." Indemnify "compensate for loss or expense" first recorded 1693.

indent (v.) --- 1385, from O.Fr. endenter "to notch or dent, give a serrated edge to," from L.L. indentare "to crunch," from L. in- "in" + dens (gen. dentis) "tooth" (see tooth). The printing sense is first attested 1676. The noun is first recorded 1596 from the verb. Extended form indentation first recorded 1728. Indenture "contract for services" first recorded 1304, from Anglo-Fr. endenture, from O.Fr. endenteure "indentation," from endenter. Such contracts (especially between master craftsmen and apprentices) were written in full identical versions on a sheet of parchment, which was then cut apart in a zigzag, or "notched" line. Each party took one, and the genuineness of a document of indenture could be proved by juxtaposition with its counterpart.

independent --- 1611, from in- "not" + dependent (q.v.). Fr. independant is attested from c.1600; It. independente from 1598. Meaning "person not acting as part of a political party" is from 1808. U.S. Independence Day (July 4) first recorded under that name in 1791.

indestructible --- 1674, from in- "not" + destructible (see destroy).

index --- 1398, "the forefinger," from L. index (gen. indicis) "forefinger, pointer, sign, list," lit. "anything which points out," from indicare "point out" (see indicate). Meaning "list of a book's contents" is first attested 1580, from L. phrases such as Index Nominum "Index of Names," index expurgatorius "specification of passages to be deleted from works otherwise permitted." The verb meaning "compile an index" is from 1720. Scientific sense (refractive index, etc.) is from 1829; economic sense (cost-of-living index, etc.) is after 1886. The Church sense of "forbidden books" is from index librorum prohibitorum, first published 1564 by authority of Pius IV.

India --- O.E., from L. India, from Gk. India "region of the Indus River," later used of the region beyond it, from Indos "Indus River," from O.Pers. Hindu, the name for the province of Sind, from Skt. sindhu "river." The more common M.E. form was Ynde or Inde, From Fr. (see Indies). India began to prevail 16c., perhaps under Sp. or Port influence.

Indian --- applied to the native inhabitants of the Americas from at least 1553, on the mistaken notion that America was the eastern end of Asia. Red Indian, to distinguish them from inhabitants of India, is first attested 1831, but not commonly used in N.Amer. More than 500 modern phrases include Indian, most of them U.S. and most impugning honesty or intelligence, e.g. Indian giver, first attested 1765 in Indian gift:

Indian summer --- spell of warm weather after the first frost, first recorded 1778, Amer.Eng., perhaps so called because it was first noted in regions inhabited by Indians, or because the Indians first described it to the Europeans. No evidence connects it with the color of fall leaves or a season of Indian attacks on settlements. It is the Amer.Eng. version of British All-Hallows summer, Fr. été de la Saint-Martin (feast day Nov. 11), etc. Also colloquial was St. Luke's summer (or little summer), period of warm weather occurring about St. Luke's day (Oct. 18).