Aftermarket (Music), Master pseudoname of projects by engineer/producer Jonathan Borsis.
Aftermarket (automotive), the addition of non-factory parts, accessories and upgrades to a motor vehicle.
After-market (general), any market where customers who buy one product or service are likely to buy a related, follow-on product. For example, customers who install a software package will constitute an after-market for software support services.
Aftermarket (finance) or
Secondary market is the financial market for trading of securities that have already been issued.
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the market for parts and supplies for machines, equipment, etc after they have been purchased.