chop [OE] In the sense ‘to cut something into small pieces’ chop is a variant of the closely related word chap [LME], ‘to become cracked and sore’. Similarly, while a choppy sea nowadays is one with the surface broken up by many small waves, in the early 17th century the adjective meant ‘full of cracks or clefts’. To chop and change is to keep changing your opinions or behaviour without warning and often for no good reason. Both chop and *change could once mean ‘barter or exchange’, and they were used in this phrase (which originally meant ‘to buy and sell’) from the 15th century onwards. As time went on, change came to be interpreted in its more usual sense, with chop reinforcing the idea of abruptness. See also chinese words.