A flower bud; the part of a plant before the flower opens.
春になると庭の桜の蕾が膨らんできた。
In spring, the cherry tree buds in the garden began to swell.
朝の散歩で、まだ堅いつぼみを見つけた。
On my morning walk I found a bud that was still hard.
雨の後、蕾がほころび始めた。
After the rain, the buds began to unfurl.
A promising young person or someone with budding talent (figurative).
彼は将来を期待される若い俳優のつぼみだ。
He is a promising young actor.
音楽界のつぼみが次々にデビューしている。
Budding talents in the music world are debuting one after another.
あの子は絵の才能があって、まだつぼみだが期待できる。
That child has artistic talent; they're still a bud but promising.