to go; to come to one's place / to (a letter) be delivered / to depart / to rely (on a method) / (年が～) to age / (うまく～) to go well / イく: (slang) to have an orgasm, to come, to cum

past tense and perfective aspect of 行く (iku) [godan]

past tense and perfective aspect of 行う (okonau) [godan]

volitional form of 行く (iku, yuku) [godan]

negative of 行く (iku, yuku) [godan]

hypothetical and imperative forms of 行く (iku, yuku) [godan]

going

behind, after

(spatially) the back, the rear, behind / (temporally) later, afterwards, some time after the present / the rest

one's backside / the back, the rear (both spatially and temporally)