Etymology: < Old French barat (nominative baras ) masculine (= Italian baratto , Old Spanish barato , Provençal barat ), also Old French barate (feminine) (= Old Spanish barata , Catalan barata , Provençal barata ) ‘deceit, fraud, confusion, trouble, embarrassment.’ Of doubtful origin: the final -at of Old French, and Italian -atto , indicate an original a in position, as -att- , -apt- (Godefroy has a 14th cent. spelling barapt ). The original sense in Romanic seems to have been ‘traffic, commerce, dealing’ (P. Meyer). Diez, Scheler, and E. Müller favour a possible derivation < Greek πράττειν ‘to practise, do business, deal,’ as to which see their works. Chevallet and Stokes compare Old Irish mrath , later brath , Old Breton brat , later brad , Welsh brad ‘betrayal, treachery,’ as the possible source of the French and thence of the other Romanic forms. Sense 3 cannot be separated from Old Norse barátta ‘fight, contest, strife, (in derivatives) trouble,’ which appears to have concurrently or independently influenced the English word.

Etymology: ? < barrat n. (in sense 3), or perhaps < barrator n.; but compare Old French barater , Old Spanish baratar , Portuguese baratar , Catalan baratar , Provençal baratar , Italian barattare to exchange, to cheat, deceive (after sense 1 of barrat n.).