Green’s Dictionary of Slang

1. (US black/drugs) intoxicated by drugs.

1989		N.Y. Times 6 Aug. 20/3: Then there are wounds inflicted with knives, baseball bats and other weapons when drug users are ‘tweaking,’ the street jargon for the volatile behavior that accompanies crack.
1997–2001		Online Sl. Dict. 🌐 tweak adj 1. to be under the influence of crank. (‘Dude, I’m tweaking.’).
2007		C. Goffard Snitch Jacket 168: You’re tweaking! I can’t believe you’re tweaking again.

2. (US campus/black) tense, emotional, hyperactive.

2001

Eble Campus Sl. Fall 11: TWEAKING – high strung, jittery, hyperactive.

3. (US black) angry.

2006

G. Pelecanos Night Gardener 244: She was tweakin after the school called.