aftermarketnoun [ C ]
also after-market uk/ˈɑːftəˌmɑːkɪt/us/ˈæftərˌmɑrkɪt/COMMERCE, PRODUCTIONthe selling of new parts for cars that have already been manufactured:
Aftermarkets for automotive parts in North America are booming.
The auto-dealer was looking for after-market auto parts.