break-dancing n.

c. 1300, "act of breaking, forcible disruption or separation," from break (v.). The sense in break of day "first appearance of light in the morning" is from 1580s; the meaning "sudden, marked transition from one course, place, or state to another" is by 1725.

The sense of "short interval between spells of work" (originally between lessons at school) is from 1861. The meaning "stroke of luck" is attested by 1911, probably an image from billiards (where the break that scatters the ordered balls and starts the game is attested from 1865). The meaning "stroke of mercy" is from 1914. The jazz musical sense of "improvised passage, solo" is from 1920s. The broadcasting sense is by 1941.

also break-down, 1832, "a collapse, a falling apart," from the verbal phrase (attested by late 14c. in the sense "take down by breaking" (trans.); 1831 in the intransitive sense "come down by breaking; 1856 as "to fail through incapacity, excess emotion, etc."); see break (v.) + down (adv.). The noun, specifically of machinery, is from 1838; meaning "an analysis in detail" is from 1936 (from the verbal phrase in the sense "analyze, classify," 1934). Also in 19c. American English "a noisy, lively dance sometimes accompanied by singing" (1864). Nervous breakdown is from 1866.