expression, noun-modifying (irregular)
well-coordinated; in sync; harmonious
Describes actions, teamwork, or performances where people move or work together smoothly, as if breathing in unison.
彼らは息の合ったプレーで観客を沸かせた。
They thrilled the audience with their well-coordinated play.
息の合ったコンビネーションで仕事を進める。
They proceed with the work in a well-coordinated combination.
From 息 (breath) + の + 合った (past tense of 合う, to match). Literally 'breaths have matched', implying synchronized breathing and, by extension, harmonious coordination.