retreating figure; back of a person walking away
Refers to the sight of someone's back as they walk away, often with a sense of loneliness or finality. Used in literary or poetic contexts.
彼の後ろ影を見送りながら、もう会えない気がした。
Watching his retreating figure, I felt we would never meet again.
Compound of 後ろ (ushiro, 'behind') and 影 (kage, 'shadow' or 'figure'). The exact historical derivation is uncertain, but the combination evokes the image of a person's shadow or silhouette as they depart.