隙

also 透き

1. noun gap; opening; room; space
2. break; interval; spare moment; spare time
3. unguarded moment; carelessness; weak spot; chink in one's armor; flaw; fault
4. chance; opportunity

げき

1. noun gap; opening; space
2. opportunity (to take advantage of); chance
3. discord; disagreement

ひま

1. noun, obsolete gap; opening; space