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

going

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

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

negative of 行く (iku, yuku) [godan]

行っていらっしゃい: alternative form of いってらっしゃい (itterasshai)

see you later (said by a person staying, a stock phrase required by the Japanese etiquette, lit.: (after) going, come back)

(humble) alternative form of いってきます (itte kimasu)

back and forth

(colloquial) Synonym of 行って来ます (itte kimasu, “see you later”)