- split (v.)
- 1580s (transitive and intransitive), not found in Middle English, probably from a Low German source such as Middle Dutch splitten, from Proto-Germanic *spl(e)it- (cognates: Danish and Frisian splitte, Old Frisian splita, German spleißen "to split"), from PIE *(s)plei- "to split, splice" (see flint).
U.S. slang meaning "leave, depart" first recorded 1954. Of couples, "to separate, to divorce" from 1942. To split the difference is suggested from 1715; to split (one's) ticket in the U.S. political sense is attested from 1842. To split hairs "make too-nice distinctions" is from 1670s (split a hair). Splitting image "exact likeness" is from 1880. To split the atom is from 1909.
- split (adj.)
- 1640s, past participle adjective from split (v.). Split decision is from 1946 of court rulings, 1951 in boxing. Split shift is from 1904. Split personality first attested 1899.
- split (n.)
- 1590s, "narrow cleft, crack, fissure," from split (v.). Meaning "piece of wood formed by splitting" is from 1610s. Meaning "an act of separation, a divorce" is from 1729. From 1861 as the name of the acrobatic feat. Meaning "a drink composed of two liquors" is from 1882; that of "sweet dish of sliced fruit with ice cream" is attested from 1920, American English. Slang meaning "share of the take" is from 1889. Meaning "a draw in a double-header" is from 1920.