More formal/written than the everyday
债 (zhài) or
欠款 (qiànkuǎn). You'll see
债款 in legal documents, news reports about corporate debt, and historical contexts (e.g. unequal-treaty
庚子赔款 indemnities). In casual speech use
欠债 (qiànzhài) 'to owe a debt' or
借的钱 (jiè de qián) 'borrowed money.'