Green’s Dictionary of Slang

tug n.

1. as a physical act.

(a) an act of sexual intercourse.

(b) [1940s–60s] (Irish) the breaking out of someone from prison.

(c) [1960s+] an arrest.

(d) [1970s] the act of picking up, meeting, introducing oneself.

(e) [1970s+] a warning.

(f) [1950s+] an act of masturbation; also as used in phrs. below.

2. (Aus.) with (derog.) ref. to a person.

(a) [1900s] (Aus.) a racecourse tipster, presumed to be fraudulent.

(b) [late 19C–1930s] a confidence trickster.

(c) a gullible fool.

(d) [1900s-20s] (chiefly Aus.) a dirty, uncouth, repellent person [? generalized use of Etonian public school jargon tug, a scholar, a clever person, a (too) hard worker; itself abbr. SE tug-mutton, a ref. to their meals but ? also to masturbation. Such figures are disdained by their aristocratic peers].

(e) [late 19C–1930s] a card-sharp [? they tug cards from the bottom of the pack].

In compounds

tug job (n.)

[2000s] (US) the masturbation of a partner.

In phrases

have a tug (v.)

[1950s+] to masturbate.