'swap' originates from Middle English, specifically the word 'swappen', likely of imitative or Germanic origin where the root suggested a quick striking or exchanging action.

'swap' changed from Middle English 'swappen' and later stabilized as the modern English verb and noun 'swap'; the noun plural form developed regularly as 'swaps'.

Initially, it likely carried a sense of a quick strike or action and then shifted to the meaning 'exchange' or 'trade' over time, which is the primary modern sense.