Roller

Part of speech: noun

Pronunciation: /ˈɹəʊlə/

Definitions

1. A round, cylindrical instrument that twists to flatten or shift materials
2. A cylindrical device used to press or smooth out materials like dough or paint ; a rotating element within machinery that supports or guides movement ; a type of footwear equipped with wheels for rolling on surfaces
3. An object shaped as a cylinder that applies pressure evenly across surfaces ; a mechanical part that turns to reduce friction or support loads ; a shoe designed with wheels attached for skating

Etymology: "Roller" is about as transparent as English compounds get: it is "roll" with the agent suffix "-er", meaning a thing that rolls or does the rolling. The "-er" ending was already productive in Middle English, and "rollere" was formed in the same way, so the word simply names whatever performs the action of rolling. The surprise lies in how far the sense has travelled. The noun now covers everything from a cylindrical pressing tool to a hair curler and a wave that breaks in a long, steady line, but the thread running through all of them is the cylinder turning over its own axis. Film credits offer a more recent example of the same idea: they were once printed on a physical cylinder that was rotated in front of the camera, which is where the "rolling" credits name comes from.

Synonyms: cylindrical, turner