(geology) Initialism of tonalite-trondhjemite-granodiorite.

(vulgar, slang) An erect penis. / Why do guys get boners when they wake up in the morning? / (vulgar, slang, figuratively) An often perverse sense of enjoyment from or predilection towards something.

(vulgar, slang) Of a man: to urinate.

plural of regulating screw