1
to notice;to realize;to realise;to become aware (of);to perceive;to sense;to suspect
彼は危険に気づいていなかった。
He was unaware of the danger.
2
to regain consciousness;to come to (one's senses);to come round
See also:
気がつく (きがつく)
Other forms
気付く 【きづく】 · 気ずく 【きづく】 (search-only kanji form) · 気附く 【きづく】 (search-only kanji form)