Green’s Dictionary of Slang

jab v.

1. (drugs) to inject drugs; thus jabbing n.

[US]S.F. Call 11 Apr. 9/5: The professor stole up behind and jabbed a hypodermic syringe into one youth’s wrist.
[US]K. McGaffey Sorrows of a Show Girl Ch. xi: It is my personal opinion that she sniffs the white. She either does that or jabs, though it don’t show on her arm.
[US]NY Tribune 13 July 7/7: he offered her cocaine and then attempted to jab the hypodermic needle into her arm.
[US]D. Maurer ‘Lang. of the Und. Narcotic Addict’ Pt 2 in Lang. Und. (1981) 104/1: To jab. To take drugs hypodermically.
[US] in Whitman Women’s Home Companion June in Hamilton Men of the Und. 214: But with all that jabbing I didn’t even get high any more.
[US]F. Paley Rumble on the Docks (1955) 57: All those guys use junk [...] every guy’s jabbin’ himself.
[US]E. Torres Carlito’s Way 80: Jab himself in the cock and in the neck.
[US]ONDCP Street Terms 12: Jab/job — To inject a drug.

2. (US campus) of a man, to have sexual intercourse.

[US]Trimble 5000 Adult Sex Words and Phrases.
[US]P. Munro Sl. U.

In compounds

jaboff (n.) (also jabpopp, jabpoppo) [pop n.1 (4a)]

(US prison) an injection of drugs; the sensation that follows it.

[US]G. Milburn ‘Convicts’ Jargon’ in AS VI:6 439: jaboff, n. A skin injection of drugs.
[US]D. Maurer ‘Argot of the Und. Narcotic Addict’ Pt 1 in AS XI:2 123/1: jaboff. The feeling of extreme exhilaration following immediately after a vein shot or a verification shot.
[US]B. Dai Opium Addiction in Chicago 200: Jabpopp, Jabpoppo. A shot of drugs.
[US]Monteleone Criminal Sl. (rev. edn).
[US]J.E. Schmidt Narcotics Lingo and Lore.