To wither, wilt, or sag (as flowers); to deflate or shrink (as a balloon); also used figuratively for hopes or enthusiasm fading. Usually written in kana.
朝は元気だった花が夕方にはしぼんでいた。
The flowers that were lively in the morning had wilted by evening.
夢がしぼむのを感じて、彼はため息をついた。
He sighed, feeling his dream deflate.
針で風船を刺してしまい、中の空気が抜けてしぼんだ。
I accidentally punctured the balloon with a pin, and it deflated.
期待がどんどんしぼんでいった。
My expectations slowly faded away.