Green’s Dictionary of Slang

1. (US teen, also split!) an excl. of surprise, frustration or apology, esp. after making a mistake.

1963		F. Kohner Affairs of Gidget 54: ‘I have no boy friend.’ ‘Aw – split!’ he said playfully. ‘Who you kiddin’?’.
2000		P. Beatty Tuff 173: ‘I’m running for City Council.’ ‘Oh snap, you really running. I thought City Council was the name of your posse.’.
2000		Ebonics Primer at www.dolemite.com 🌐 snap Definition: used to express anger or frustration Example: Oh snap, my bitch has crabs.
2002		‘Touré’ Portable Promised Land (ms.) 157: We Words (My Favorite Things) [...] Oh, snap! True dat! Holla back. Say what?
2005		W.D. Myers Autobiog. of My Dead Brother 98: ‘That’s the time you and me and Calvin went down to Atlantic City with Calvin’s parents—’ ‘Snap! And Calvin stood on the boardwalk and said he could see Africa and we believed him!’.
2013		W.D. Myers Cruisers: Oh, Snap! 78: Caren said. ‘You could all be accessories after the fact.’ ‘Oh, Snap!’ .
2022		J. Hannaham Didn’t Nobody Give a Shit 48: Oh, snap, where the fuck my ass even been?

2. (US black) an excl. representing (or accompanied by) snapping one’s fingers towards someone in order to express anger or disappointment; thus snap someone off v., the act of so doing.

1972

B. Rodgers Queens’ Vernacular 186: snap somebody off 1. to convey displeasure by directing a loud fingersnap towards the offending party. The closer the snap is made to the offender’s face, the larger the contempt. ‘Snap that, toad!’ = take that!