‘身心俱疲’ literally means 'body and mind both exhausted' — it describes a state of deep, all-encompassing weariness affecting both physical energy and mental resilience. The four characters work together: 身 (body), 心 (mind/heart), 俱 (both, all), and 疲 (tired, fatigued). Unlike simple fatigue (e.g., 累), this phrase emphasizes simultaneous depletion across two essential dimensions of human well-being.

This expression is commonly used in formal writing, medical contexts, or empathetic speech to convey serious exhaustion — often resulting from prolonged stress, caregiving, chronic illness, or intense emotional strain. It carries a tone of gravity and sympathy; speakers use it not for everyday tiredness after work, but for profound depletion that impairs daily functioning. While grammatically an adjective, it typically functions predicatively (e.g., 他身心俱疲) or as a subject complement after 是 or 很.