Other forms: backing, backed, backs
Back is mostly a direction, not a body part. It points at where you came from and sends you there again: come back, go back, put it back, call me back. Nearly every time you hear the word, that is the job it is doing.
It is also the part of you that aches after lifting something heavy, and the part of anything that faces away from you — the back of the house, the back of the bus, the back of an envelope. And it turns into a verb meaning to support: the bank backed the loan, her family backed her decision. Watch for behind somebody's back, which means doing the thing precisely where they cannot see it.
1adverbagainTo or towards the place or the state that something was in before.~53%
“She went back to the shop for the receipt.”
2adverbbehindAt or towards the part that is furthest from the front.~12%
“The children sat right at the back of the bus.”
3nounbackThe body part you lie on when you sleep facing the ceiling.~12%
“He hurt his back lifting the box.”
4nounrearThe part of something furthest from the front.~17%
“The garden is at the back of the house.”
5verbsupportTo support a person or a plan, with money or with words.~6%
“Two of the directors backed her proposal.”
Shares are an estimate: a language model read 24 sentences found in the wild and placed 17 of them on a sense (7 were unclear) — a count of our sample, not a measurement of English.
Middle English
bak
English, today
back
From Middle English bak. From Middle English bak, from Old English bæc, from Proto-West Germanic bak, from Proto-Germanic baką, possibly from Proto-Indo-European bʰeg- (“to bend”). The adverb represents an aphetic form of aback. Compare Middle Low German bak (“back”), from Old Saxon bak, and West Frisian bekling (“chair back”), Old High German bah, Swedish - and Norwegian bak. Cognate with German Bache (“sow [adult female hog]”).
Etymology from Wiktionary, CC BY-SA