Green’s Dictionary of Slang

third adj.

SE in slang uses

In compounds

third base (n.) [baseball imagery]

(US) contact with the vagina or penis, in the context of sexual exploration (cf. first base n. (1); second base under second adj.; home run n. (2)).

[US](con. 1944) N. Mailer Naked and Dead 551: I got to third base last night.
Little Blue Patakha on Urban Dict. 🌐 Third Base The last base before sex, entailing contact with the main sexual regions, a handjob or a blowjob (fellatio) for guys and fingering or giving head (cunnilingus) to the girl. ‘We got all the way to Third Base on my friend’s roof when I bent down to give him his first blowjob ever.’.
[US] posting at 8 Nov. 🌐 We had been just hitting third base (kiss/feel).
third beer (n.)

(N.Z.) a woman, generally, a girlfriend, who is considered plain and unexciting.

[NZ]McGill Reed Dict. of N.Z. Sl. 211: third beer A woman, usually a girlfriend, who is not attractive or very exciting; dull, ordinary.
third degree

see separate entries.

third leg (n.)

the peni; thus on three legs, having an erection.

[[UK]Harris’s List of Covent-Garden Ladies 69: [She] is so very careful of her health, that befopre she receives her guinea, she must examine every one of her partner’s legs].
[Aus]Satirist & Sporting Chron. (Sydney) 25 Feb. 2/1: The hon. Attorney General wished to give his half for any benevolent purpose — [...] from what we can gather, he is only anxious to give his third (q. leg) to such charitable purposes - of that anon.
[US]R.A. Wilson Playboy’s Book of Forbidden Words.
[US] P. Munro Sl. U.
[US]Randolph & Legman Ozark Folksongs and Folklore I 452: The penis [...] often frankly called in American children’s slang, the third leg or middle leg.
[UK]B. Dark Dirty Cockney Rhy. Sl. 82: Mystic Meg third leg.
[UK]Guardian Rev. 6 Aug. 13: He calls it his ‘third leg.’.
[Aus]R.G. Barrett Rosa Marie’s Baby (2013) [ebook] Uriah ogled Tania [...] then hobbled off to the residence on three legs.
[US]F. Bill Donnybrook [ebook] Liz [...] winked at Pete and the girth of his third leg.
Harlem Spartans ‘Hazards’ 🎵 She lucky if she get third leg.
third man (n.)

(N.Z. prison) a getaway driver.

[NZ]D. Looser Boobslang [U. Canterbury D.Phil. thesis] 188/2: third man n. (in a criminal job) the person who drives the ‘getaway car’.
third rail

see separate entries.

third sexer (n.) [SE third sex, homosexuality, coined by sexologist Magnus Hirschfeld (1868–1935)]

(US) a homosexual.

[[UK]Variety 26 Aug. n.p.: Another exceptionally sordid phase of night life [is] what a prominent play broker calls ‘the third sex‘ [...] These girlish boys and manly women [etc] ].
[US]R.O. Scott Gay Sl. Dict. 🌐 third-sexers: [1930s New York] Homosexuals.
third-tierer (n.)

(US) a prostitute who cruised the third tiers of theatres.

Wag (N.Y.) 7 Dec. 2/3: One of the saints of Dr. S---’s Church, whoat [sic] used to be a third tierer in all the southern theatres.
third-world briefcase (n.) [SE third-world, i.e. non-white]

a large portable stereophonic tape deck/radio, particularly popular among black youths in the US and UK.

Minneapolis Star (MN) 9 June 27/1: Now, whites who once disparaged the boxes with such nicknames as ‘ghetto blasters’ and ‘third world briefcases’ are flocking to buy the units.
[Aus]R.G. Barrett You Wouldn’t Be Dead for Quids (1989) 87: And I’ll shove that fuckin’ Third World briefcase up there [i.e. ‘your arse'] as well.
[UK]Guardian 23 Feb. 27/4: A number of the portables (a.k.a. Ghetto Blasters or Third World Briefcases) are beginning to sprout extra buttons.
[US]Eble Campus Sl. Fall.
Urban Dict. 🌐 wog box A large stereo carried held to the ear by some tinted folk. Also 3rd world briefcase. I saw one of those new wog boxes in Dixons that puts out about 100 watts.
[US]G.P. Pelecanos Firing Offense 63: ‘What did he steal?’ ‘A third world briefcase, what else? [. . . .] He lost his job for a boogie box’.

In phrases