noun
Literary word for a very brief moment; almost exclusively used in the fixed expression 寸陰を惜しむ (to make the most of every moment).
彼は寸陰を惜しんで勉強した。
He studied, making the most of every moment.
「寸陰を惜しむ」という言葉は、時間を大切にする意味だ。
The phrase 寸陰を惜しむ means to value one's time.