(plī) v. plied, ply·ing v.t.
To bend; mold; shape.
—v.i. Obs. To bend or yield.
—noun plural plies
1. A web, layer, fold, or thickness, as in a carpet, cloth, etc.
2. A strand, turn, or twist of rope, yarn, thread, etc.: used in combination to mean (a certain) number of folds, twists, or strands: three-ply yarn.
3. A bent or bias; inclination to one side, as of the mind. [<F plier <L plicare]

(plī) v. plied, ply·ing v.t.
1. To use in working, fighting, etc.; wield; employ.
2. To work at; be engaged in: He plies the trade of shoemaker.
3. To subject to repeated action, as by offering unwanted gifts, asking questions insistently, etc.: to ply a person with drink; to ply one with requests.
4. To strike or assail persistently: He plied the donkey with a whip.
5. To traverse regularly: ferryboats that ply the river.
—v.i.
6. To make regular trips; sail: usually with between.
7. To work steadily; do one's or its work.
8. Poetic To proceed; steer.
9. Naut. To beat; tack. [Aphetic var. of APPLY]