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gap; opening; room; space
break; interval; spare moment; spare time
unguarded moment; carelessness; weak spot; chink in one's armor; flaw; fault
chance; opportunity
敵の隙を見つけて攻撃を仕掛けた。
I found an opening in the enemy and attacked.
ドアの隙から冷たい風が入ってくる。
Cold wind comes in through the gap in the door.
彼女には隙がなくて完璧に見える。
She has no openings and looks perfect.