"flat ring for sealing joints or holding nuts," mid-14c., generally considered an agent noun of wash (v.), but the sense connection is difficult, and the noun may derive instead from the ancestor of French vis "screw, vise" (see vise).
washer (n.1)
1520s, "person who washes," agent noun from wash (v.). From 1808 as "machine that washes." Washer-woman is from 1630s; earlier wash-woman (1580s).
权威例句
1. Make sure the washer is firmly seated before tightening the pipe.
旋紧水管之前,检查一下洗衣机是否已牢牢地固定在底座上了.
2. They will introduce a new washer to the public.