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the harmonizing, mentally and physically, of two parties engaged in an activity; singing from the same hymn-sheet; dancing to the same beat
あうんの呼吸で連携できた。
We coordinated in perfect sync.
二人はあうんの呼吸だ。
The two are in perfect harmony.
あうんの呼吸でパスを回した。
We passed the ball in perfect sync.