noun
moment's leisure; free minute
Refers to a very short period of free time, often used in expressions like 寸暇を惜しむ (to make the most of every spare moment).
彼は寸暇を惜しんで勉強した。
He studied hard, making the most of every spare moment.
寸暇を利用して散歩する。
I take a walk whenever I have a free minute.