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to leave (a matter, decision, etc. to someone); to entrust (to someone); to entrust (someone) with
to leave (to chance, one's imagination, etc.); to let (take its own course); to let (happen); to give (oneself to something)
to use (money, strength, spare time, etc.) to the full; to use freely; to use without reserve
この件は部長に委せることにした。
I decided to leave this matter to the department head.
料理の味付けは母に委せている。
I leave the seasoning to my mother.
判断を専門家に委せるのが一番だ。
Leaving the decision to an expert is the best move.