-ply

Definitions

General English

  • verb
    (written as ply)
    to go backwards and forwards

Cars & Driving

Construction

  • (written as ply)
    A single layer or sheet of veneer.
  • (written as ply)
    One complete layer of veneer in a sheet of plywood.

Publishing

  • suffix indicating the number of layers of paper or board which are glued together to give greater strength

Origin & History of “-ply”

English has two distinct words ply, although ultimately they are related. The one meaning ‘fold, twist, layer’ (14th c.), now mainly found in plywood (20th c.) and in combinations such as two-ply and three-ply, comes from Old French pli, a derivative of the verb plier ‘bend, fold’ (source of English apply (14th c.), pliable (15th c.), pliant (14th c.), pliers (16th c.), and reply). this went back to Latin plicāre ‘fold’, a relative of English fold and source of accomplice, complicate (17th c.), employ, explicit, imply, pleat, plight ‘predicament’, and supplicate. It was formed from a base that also produced English perplex (16th c.) and the final syllables of simple and supple. The apple pie of apple-pie bed (18th c.) is thought to be an alteration of French nappe pliée ‘folded sheet’.

Ply ‘travel a route regularly’ or ‘solicit’ (as in ‘ply for hire’) (14th c.) is short for apply, a relative of ply ‘fold’, and originally meant ‘apply, employ’ (as in ‘ply one’s needle’).
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