Green’s Dictionary of Slang

jab n.

[note earlier jab v. (1)]

1. an injection.

(a) (drugs) an injection of a narcotic drug.

[US]St Paul Globe (MN) 4 Dec. 20/4: He was a confirmed victim of the needle, and required rather regular jabs to keep keyed up to the notch.
[US]Anderson Intelligencer (SC) 30 July 2/4: Opium is a popular drug and almost any form of ‘hop’ is relished. The left arm of a black prisoner [...] was fearfully lacerated by continued jabs from a hypodermic syringe.
[US]Jackson & Hellyer Vocab. Criminal Sl. 48: jab [...] current amongst morphine and cocaine fiends. A hypodermic injection.
[US]M. West Drag (1997) Act II: She needed a jab. She’s been taking heroin and morphine by the barrels.
[US](con. 1920s) C.W. Willemse Behind The Green Lights 351: Wild for a sniff or a jab, he sees on your desk a package of cocaine, heroin or morphine.
[US]Monteleone Criminal Sl. (rev. edn).
[US]J.E. Schmidt Narcotics Lingo and Lore.
[US]Ragen & Finston World’s Toughest Prison 805: jab – A hypodermic injection.
[NZ]D. Looser Boobslang [U. Canterbury D.Phil. thesis] 94/1: jab n. 2 a hypodermic injection.

(b) (orig. milit.) an inoculation, any form of injection, esp. against diseases such as TB and polio.

[UK]G. Kersh They Die with Their Boots Clean 51: First time that feller got a Jab, he went out like a light.
[NZ]G. Slatter Gun in My Hand 59: Men lining up for jabs.
[Aus]B. Humphries Traveller’s Tool 32: There are no jabs necessary for Australia.
[UK]M. Dibdin Dying of the Light 13: They’ll stop your meals! They’ll give you jabs!
[UK]Indep. on Sun. 9 Jan. 3: You should go to your GP and get a flu jab.

2. (US) in fig. use, an attempt, a try.

[US]E.H. Babbitt ‘College Words and Phrases’ in DN II:i 43: jab, n. An attempt at anything.
[Aus]K. Tennant Battlers 174: I’ll be with the first to take a bayonet and have a jab at old Hitler.

3. (US/Irish) an act of copulation.

[US]C. Loken Come Monday Morning 128: Even if he got drunk enough endin’ up givin’ ole mattressback Carol a fast jab or two.
[UK]F. Pitt-Kethley Sky Ray Lolly 28: Lying till sex becomes / duty, a daily pinta, Sunday joint / or yearly jab?
[Ire]P. McCabe Breakfast on Pluto 1: I’ll leave the door open tonight and you can all troop in and give me a jab.

4. (N.Z. prison) a hypodermic syringe.

[NZ]D. Looser Boobslang [U. Canterbury D.Phil. thesis] 94/1: jab n. 1 needle.

5. (Irish) a woman’s breast; usu. in pl.

[Ire]G. Coughlan Everyday Eng. and Sl. 🌐 Jabs (n): breasts.

In phrases

big jab (n.) (also stainless steel ride)

(US prison) a lethal injection, used in executions.

[US]Other Side of the Wall: Prisoner’s Dict. July 🌐 Big Jab: Lethal injection. Also, ‘stainless steel ride,’ ‘doctorate in applied chemestry,’ [sic] or the ‘needle.’.