DIAGONAL CREDIT SPREAD - A type of calendar spread. It is a debit transaction where options are purchased in a nearer expiration and options of the same type are sold in a farther expiration, on the same underlying. It is diagonal because the options have different strike prices. DIAGONAL DEBIT SPREAD - Type of calendar spread. It is a credit transaction where options are sold in a nearer expiration and options of the same type are purchased in a farther expiration, on the same underlying. It is diagonal because the options have different strike prices.
