Transaction
late Middle English (as a term in Roman Law): from late Latin transactio(n- ), from transigere ‘drive through’ (see transact).
wiktionary
From Middle French, from Old French transaccion, from Late Latin transactio.
etymonline
transaction (n.)
mid-15c., "the adjustment of a dispute, a negotiated agreement, management or settlement of an affair," from Old French transaccion "exchange, transaction," from Late Latin transactionem (nominative transactio) "an agreement, accomplishment," noun of action from past-participle stem of transigere "stab through; accomplish, perform, drive or carry through, come to a settlement," from trans "across, beyond; through" (see trans-) + agere "to set in motion, drive, drive forward," hence "to do, perform" (from PIE root *ag- "to drive, draw out or forth, move"). Meaning "a piece of business" is attested from 1640s. Related: Transactions; transactional.
