Burl

Part of speech: noun (n.)

1. A knot or lump in thread or cloth.

2. An overgrown knot, or an excrescence, on a tree; also, veneer made from such excrescences.

Part of speech: verb (v.)

To dress or finish up (cloth); to pick knots, burs, loose threads, etc., from, as in finishing cloth. Burling iron, a peculiar kind of nippers or tweezers used in burling woolen cloth.