trade (something) in on (something)

trade (something) in on (something)

To exchange a used item for a new one, typically by using the proceeds from its sale to pay for a portion of the price of the new item. My brother trades his car in on a new one every year. He loves to have the newest model on the market. I always used to trade in my old video games on new ones when I was a kid.
See also: on, trade