Old English wascan, wæscan, from Proto-Germanic *watskanan (cf. Old Norse vaska, Middle Dutch wasscen, Dutch wassen, German waschen), from stem *wat-, the source of water. Related: Washed; washing. Used mainly of clothes in Old English (the principal verb for washing the body, dishes, etc. being þwean). Washed-out "faded" is from 1837. Washed up is 1923 theater slang, from notion of washing up at the end of a job.
late Old English wæsc "act of washing" (see wash (v.)). Meaning "clothes set aside to be washed" is attested from 1789; meaning "thin coat of paint" is recorded from 1690s; sense of "land alternately covered and exposed by the sea" is recorded from mid-15c.
v. washed, wash·ing, wash·es
To cleanse, using water or other liquid, usually with soap, detergent, or bleach, by immersing, dipping, rubbing, or scrubbing.
To make moist or wet.
The act or process of cleansing or washing.
A solution used to cleanse or bathe a part.
To prove acceptable; bear testing •Usually in the negative: Well, it just won't wash/ The stereotype of gay males as child molesters just doesn't wash any more/ That washes. I'll buy it (1849+)
[verb sense said to be fr a defective printed calico that could not be washed; third noun sense perhaps fr the notion that equal opposing elements wash each other out or away, or wipe the slate clean]