trade-in noun 2trade in verb 1forms 4 noun2 •property used as part payment for a new purchase •a transaction including such paymentThe Alco design, although the least powerful of the three, claims an economy advantage in its use of a V-12 engine instead of the usual V-16; moreover, Alco offers excellent trade-in terms. — 1962 trade in verb1 •To give a piece of merchandise as part of the payment or trade for something new. formstraded in · trading in · trades in · trade-ins