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to stifle a smile, yawn, etc.
to bite to death
彼はあくびを噛み殺した。
He stifled a yawn.
学生は厳粛な場で笑いを噛み殺して耐えた。
The student stifled a laugh in the solemn setting.
女優はカメラの前で涙を噛み殺すことを学んだ。
The actress learned to stifle tears in front of the camera.