From Old French 'barater' (to exchange, to cheat) — the word carried connotations of deception, reflecting suspicion of moneyless trade.
To exchange goods or services for other goods or services without using money; the system or act of such exchange.
From Old French 'barater' (to cheat, to deceive, to exchange, to barter), of uncertain ultimate origin. Possibly from Greek 'prattein' (to do, to practice, to trade) via a Vulgar Latin intermediary, or from Celtic sources. The Old French word carried a strong sense of trickery and fraud alongside the neutral meaning of exchange — early barter was assumed
The word 'barter' originally implied cheating. Old French 'barater' meant both 'to trade' and 'to deceive,' and the related legal term 'barratry' (habitual bringing of frivolous lawsuits, or fraud by a ship's captain) preserves the dishonest sense. The assumption embedded in the word is that moneyless exchange was inherently shifty — if you were not paying cash, you were probably trying