harpoon, n. — Green’s Dictionary of Slang

harpoon n.

1. (US) ridicule or victimization.

1914

Jackson & Hellyer Vocab. Criminal Sl. 43: harpoon [...] A metaphor for lampoon.

2. the penis.

1980

Maledicta IV:2 (Winter) 194: A pointed weapon may be involved, such as a pike, prong, pronger, harpoon.

3. a hypodermic syringe, as used by drug addicts.

1938		D. Maurer ‘Lang. of the Und. Narcotic Addict’ Pt 2 in Lang. Und. (1981) 103/2: harpoon. The hypodermic needle.
1949		Monteleone Criminal Sl. (rev. edn).
1959		J.E. Schmidt Narcotics Lingo and Lore.
1997		E. Little Another Day in Paradise 18: Just keep digging around in your fingers with that fuckin’ harpoon.
2001		D. Looser Boobslang [U. Canterbury D.Phil. thesis] 85/1: harpoon n. a hypodermic syringe and needle.

get the harpoon (v.)

throw the harpoon in(to) (v.) (US)

1. to persuade, to trick, to attack.

1896		Ade Artie (1963) 56: You ought o’ seen him when Mame’s mother started to throw the harpoon into him.
1903		A.H. Lewis Boss 196: He comes up for renomination within two months. He’d look well throwin’ the harpoon into me right now, wouldn’t he?
1905		H. Green Actors’ Boarding House (1906) 200: We’ll throw the harpoon into her old man and shake him down to a fare-you-well.

2. to interrogate aggressively.

1909

H. Green Mr. Jackson 160: I stood pat when they throwed the harpoon into me in the inspector’s room.

3. to have sexual intercourse (with).

1966

in G. Legman No Laughing Matter 332: I’m going to [...] throw the harpoon into that blonde stewardess in the back cabin.