Etymology
1. O.E.
bæc "back, backwards, behind," from P.Gmc.
*bakam (cf. O.S., M.Du.
bak, O.Fris.
bek), which mostly has been ousted in other modern Gmc. languages by words akin to Mod.E.
ridge. Verb "to move (something) back" is from 1486; meaning "to support" (as by a bet) is first attested 1548.
Backbiting is first recorded c.1175;
backslide in the religious sense is from 1581;
backwoods is from 1709.
Back-date first recorded 1946.
Backside "rump" is first recorded 1500.
Back door "devious, shady, illegal" is from 1643. The verb
back off "retreat" is attested from 1930s.
Back down in fig. sense of "withdraw a charge" is first attested 1859, Amer.Eng., from notion of descending a ladder, etc.
Back-firing "premature ignition in an internal-combustion engine" is first recorded 1897.
Back-stabber in the fig. sense is from 1906.
Back-seat driver first attested 1926.
Back-track "retrace one's steps" is from 1904.
Back-to-nature (adj.) is first attested 1915.
Backpack is 1914 as a noun, 1916 as a verb. The
back of (one's) hand has been used to imply contempt and rejection since at least 1300; to
know something like the back of one's hand, implying familiarity, is first attested 1943.
Back bench in the House of Commons sense is from 1874.
Back-hand as a tennis stroke dates from 1657.
Back-talk "impertinent retort" is first recorded 1858, originally often used in literary attempts at low Irish idiom. To be
on the back burner in the figurative sense is from 1960.
Back-formation coined by Eng. lexicographer James Murray (1837-1915).
2. Etymology tree
3. Proto-Indo-European *bʰeg-der.?
4. Proto-Germanic *baką
5. Proto-West Germanic *bak
6. Old English bæc
7. Middle English bak
8. English back
9. 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.
10. 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]”).
Verbs referencing "back"
Welsh
bacio, Danish
bakke, Norwegian
bakke, Icelandic
bakka.