Pronunciation: (af'tur mär"kit, äf'-),[key] —n. 1. the market for replacement parts, accessories, and equipment for the care or enhancement of the original product, esp. an automobile, after its sale to the consumer: The company holds a large share in the automotive radio aftermarket. 2. any additional market created by a product after the primary market: Television is the perfect aftermarket for old movies. 3. Stock Exchange.See secondary market.