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to hold back (e.g. emotions); to rein in (e.g. a horse, unruly people); to bridle
to get the better of
to control; to command
警備員が暴れる男を取り押さえて制した。
The security guard restrained and subdued the violent man.
決勝戦を制して優勝旗を手に入れた。
We won the final and got the championship flag.
感情を制することが大切だ。
It's important to keep one's emotions in check.