過去【かこ】
the past, bygone days, one's past (that one would prefer remained secret), past (tense), preterit, preterite, previous life
死去【しきょ】
death, decease, passing away
撤去【てっきょ】
removal, taking away, dismantling (a building, facilities, etc.), withdrawal (of troops)
去年【きょねん】
last year
去る【さる】
to leave, to go away, to pass, to elapse, to be distant, to send away, to drive off, to divorce, to (do) completely, last ... (e.g. "last April")
逝去【せいきょ】
death, passing
去来【きょらい】
coming and going, recurring (esp. thoughts)
立ち去る【たちさる】
to leave, to depart, to take one's leave