Aftermarket (noun)

1. The market for spare parts, accessories, or components for a product, especially a vehicle, after its original sale.
2. The market for securities or commodities after the initial public offering or sale.

Origin:

Late 19th century: from after + market.

Examples:

1. The aftermarket for the car was thriving, with many options for customization and improvement.
2. The aftermarket for the stock was volatile, with prices fluctuating rapidly.
3. The aftermarket for the phone was booming, with many new cases and screen protectors available.
4. The aftermarket for the product was disappointing, with few upgrades or additions available.
5. The aftermarket for the commodity was stable, with prices remaining consistent.