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(a person's) appearance from behind; person as seen from behind; back view; retreating figure
母の後ろ姿を見送った。
I watched my mother's back as she left.
彼の後ろ姿が遠ざかっていった。
His figure from behind grew smaller in the distance.
夕日に映る後ろ姿が寂しそうだった。
The silhouette from behind, lit by the setting sun, looked lonely.