ply

Travel a route regularly.

“Ships ply the waters near the coast”

Give what is desired or needed, especially support, food or sustenance.

Apply oneself diligently.

Join together as by twisting, weaving, or molding.

“ply fabric”

Use diligently.

“ply your wits!”

Wield vigorously.

“ply an axe”

One of the strands twisted together to make yarn or rope or thread; often used in combination.

“three-ply cord”

“four-ply yarn”

(usually in combinations) one of several layers of cloth or paper or wood as in plywood.