›[C or U]a way of buying a new car, machine, computer, etc. that involves giving your old one as part of the payment for it: Second-hand car prices have fallen, resulting in lower trade-in values for buyers. → See alsopart exchangenoun
›[C] an old car, machine, computer, etc. that you give as part of the payment when you buy a new one: All our stores take cars as trade-ins.