1690s, "having the hand turned backward;" see back (adv.) + hand (n.). By 1894 in reference to handwriting that flows at a back-slant. As a verb, by 1857. As a noun, in reference to tennis, 1890, short for backhand stroke or volley. The figurative adjectival sense of "indirect" is from c. 1800. Related: Backhanded; backhanding.
backfire
backflip
back-formation
backgammon
background
backhand
backhanded
backhoe
backing
backlash
backless