to twist (strands of rope or yarn) together [Middle English plien to fold, via early French plier from Latin plicare]
a strand in a yarn, wool, etcany of several layers of cloth usu sewn together or sheets of wood laminated together(used before a noun) specifying the number of strands or layers something has two-ply wood four-ply woolinformal = plywood
verb transto use (a tool, etc) steadily and diligently He was busily plying his axeto practise or perform (an occupation) steadily and diligently He's been plying his trade for over thirty yearsto keep furnishing or supplying something to (somebody) She plied them with drinksto keep asking (somebody) questions Once he'd been rescued, he was plied with questions by the presssaid of a ship, taxi, etc: to go or travel over or on (a specified route) regularly verb intranssaid of a boatman, taxi driver, etc: to wait regularly in a particular place for custom The streets were packed with taxis plying for hire(+ between) to travel regularly There's a ferry that plies between the islands [Middle English plien, short for applien: see apply]