aftermarket

From after- +‎ market.

aftermarket (plural aftermarkets)

1. (business) The market for further goods and services, such as replacement parts and accessories, subsequent to the sale of a product such as an automobile or computer.
2. (business) The industry that serves that market.
3. (finance) Trading activity in a security immediately following its initial offering to the public.

• (antonym(s) of “business”): OEM

aftermarket (third-person singular simple present aftermarkets, present participle aftermarketing, simple past and past participle aftermarketed)

1. (business) To sell goods or services in the aftermarket.

• (financial): secondary market