たいきばんせい
great talents mature late
Expression
彼かれは大器晩成たいきばんせいだ。
He's a late bloomer.
大器晩成たいきばんせいの大物おおものと言いわれて久ひさしいけど、彼かれ、いつになったら化ばけるのかね。
I haven't heard anyone call him a late bloomer in a while. But I do wonder when he's going to grow up.