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to crush to death; to press to death; to squeeze to death
to suppress (a laugh, one's anger, etc.); to stifle; to subdue (one's voice); to hold (one's breath)
彼は感情を押し殺した。
He suppressed his emotions.
笑いが込み上げるのを必死に押し殺している。
He is desperately holding back the laughter welling up inside him.
感情を押し殺す人も世の中には多い。
There are many people in this world who suppress their feelings.