waulk means to make cloth (especially tweed in Scotland) denser and more felt-like by soaking and beating. Lexicurio rates it Sui generis — a strength score of 87 out of 100.
Why “waulk” is a great word
WAULK — [Verb] To make cloth, especially tweed, denser and more felt-like by soaking, kneading, and beating it. From Middle English walken, from Old English wealcian ("to roll up, muffle up"), from Proto-West Germanic *walkōn, from Proto-Germanic *walkōną ("to roll about, full [cloth]"). Cognate with Scots waulk, Dutch walken, German walken, Danish valke, Swedish valka. Doublet of walk. The variant spelling 'waulk' is recorded from the 16th century. Unlike "full" (the general English term for the thickening process) or "walk" (its modern, pedestrian doublet), waulk is the specific, sturdy Scots variant, retaining the ancient sense of labor upon material. It is the rhythmic thud of fabric on the board, the steamy scent of damp wool in a bothy, and the slow alchemy where loose weave becomes weatherproof garment—a patient, physical argument against the world’s unraveling.
Etymology
From Middle English walken, from Old English wealcian (“to roll up; muffle up”), from Proto-West Germanic *walkōn, from Proto-Germanic *walkōną (“to roll about; full (cloth)”).
Cognate with Scots waulk (“to full”), Dutch walken (“to full”), German walken (“to full”), Danish valke (“to full”), Swedish valka (“to full”). Doublet of walk.
verb
- to make cloth (especially tweed in Scotland) denser and more felt-like by soaking and beating.“The frame on which the cloth is waulked is a board some twelve to twenty-four feet long and about two feet broad, grooved lengthwise along its surface.”