thin plate with a hole, normally used to distribute the load of a threaded fastener
Assorted washers: flat, split, star and insulating
A washer is a thin plate (typically disk-shaped, but sometimes square) with a hole (typically in the middle) that is normally used to distribute the load of a threaded fastener, such as a bolt or nut. Other uses are as a spacer, spring (Belleville washer, wave washer), wear pad, preload indicating device, locking device, and to reduce vibration (rubber washer).
Discovered by embedding cosine similarity (sentence-transformers MiniLM, 384-dim).