Green’s Dictionary of Slang

booya! excl.

also booyah!
[SE excl. boo! + yah]
(US black/campus)

1. a term used to indicate suddenness or surprise.

[US]P. Munro Sl. U. 43: The car hit us and booyah, my head flew into the windscreen.
[US]E. Little Another Day in Paradise 18: Ya turn on the tube and boo-ya you got cartoons. [Ibid.] 22: Boo-ya, you’re in the pen.

2. an echoic term used to imitate the sound of a shotgun being fired.

[US]L. Bing Do or Die (1992) 124: He hoists the imaginary shotgun, squints down the barrel — ‘Booyah! You dead.’.
[US]Dr Dre ‘187’ 🎵 Boo-yaa! Boo-yaa! then I fade into the wind. 1-8-7 and it’s on again.
[US]J. Stahl Permanent Midnight 273: BOO-YAH! – that awful brain-rattling sound of the shotgun.
[US]‘Touré’ Portable Promised Land (ms.) 157: We Words (My Favorite Things) [...] Daddy-o. Day-o! Boo-ya!
[US]C. Eble (ed.) UNC-CH Campus Sl. 2011 1: BOO-YAH! — expression of victory, jubilation, celebration: ‘Boo-yah! I made a 98 on my chem exam’.

3. an excl. denoting ‘I told you so!’.

[US]Hope College ‘Dict. of New Terms’ 🌐 booyah interjection Said to express a feeling of domination by an individual who has just done something significantly good, while competing against another individual, especially in sports or video games.
[US]Ebonics Primer at 🌐 boo-yah Definition: an exclamation that means ‘I told ya so’ Example: Hey Bitch, Boo Yah!
[US]Teen Lingo: The Source for Youth Ministry 🌐 boo-yah! 1. An exclamation used in celebrating a victory. ‘Boo-Yah! I whooped you in dat basketball game!’ 2. an expression added at the end of a short, insulting speech. Used like ‘So, there!’.

4. a greeting.

[US]Eble Campus Sl. Apr.