欠债 (qiàn zhài) literally means 'to owe debt' — 欠 (qiàn) means 'to owe' or 'to lack', and 债 (zhài) means 'debt' or 'loan'. Together, they form a verb phrase meaning 'to be in debt' or 'to owe money to someone'. It emphasizes the state or action of having unpaid financial obligations, often implying urgency or seriousness. Unlike the noun 债务 (zhàiwù, 'debt' as a concept), 欠债 is primarily used as a verb in everyday speech and writing.

This term commonly appears in discussions about personal finance, family responsibilities, business dealings, or moral accountability. It carries a slightly negative or weighty connotation — suggesting burden, pressure, or social expectation to repay. While it can be used neutrally in factual statements (e.g., 'He owes money'), context often implies concern, warning, or consequence if left unresolved. It's frequently paired with verbs like 还 (huán, 'to repay') or 累积 (lěijī, 'to accumulate') to describe debt dynamics.