The Denim Glossary: 35 Terms Every Jeans Lover Should Know

Whiskers: horizontal fade lines at the hips and crotch.
Honeycombs: fade patterns behind the knees.
Stacks: bunched fabric at the ankle that creates fade rings.
Roping: the twisted, wavy fade along a chain-stitched hem.
Train tracks: fade lines along the outseam on selvedge jeans.
Crotch blowout: the most common failure in jeans ( why it happens ).

Denim has its own language, and product pages love to use it. Here's a plain-English glossary of the terms you'll come across most.

Fabric and weaving

Twill: the diagonal weave that gives denim its strength and visible slanted lines.
Warp: the lengthwise yarns. In denim, these are dyed indigo.
Weft: the crosswise yarns, usually left undyed, which is why jeans are paler inside.
Right-hand twill: the most common weave; the diagonal runs up to the right.
Left-hand twill: the diagonal runs up to the left, giving a softer feel.
Broken twill: the diagonal alternates direction, which reduces leg twist.
Selvedge: a self-finished fabric edge made on shuttle looms (full guide).
Slub: deliberate irregularities in the yarn that give a textured surface.
Ounce (oz): fabric weight per square yard. 12–14oz is the everyday sweet spot.

Indigo: the classic blue dye (why it fades the way it does).
Rope dyeing: dipping twisted ropes of yarn repeatedly in indigo, leaving the core white.
Ring-dyed: yarn dyed only on the outside, the reason denim fades so beautifully.
Sulphur dye: used for black and coloured denim, often over-dyed with indigo.
Raw / dry: denim that hasn't been washed after weaving (raw vs washed).
Rinse wash: a single light wash to remove starch and pre-shrink.
Stonewash: washing with pumice stones to soften and fade.
Sanforised: pre-shrunk by a mechanical process, so jeans won't shrink much at home.
Unsanforised: not pre-shrunk. Expect real shrinkage in the first soak.
Loomstate: fabric straight off the loom, completely untreated.