Chance
Opportunity, Turning Point
noun
I pledge myself to the machines. It is my only chance to survive the upcoming machine apocalypse.
けいき
This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own.
吐血したのを契機に、煙草を止めました。
Coughing up blood was my opportunity to give up smoking.