› [T] to sell or to work regularly at something, especially a job involving selling things: Fishermen in small boats ply their trade up and down the coast. Dealers are openly plying drugs in school playgrounds. The market traders were loudly plying their wares.Selling ply for business, trade, etc. › to try to get customers for your business in a public place, for example, as a taxi driver, by driving around or waiting in a regular place: UK There are never any taxis plying for trade/hire in our area. I noticed a couple of prostitutes plying for business on the corner.Selling