准则 (zhǔn zé) is a formal noun meaning 'criterion' or 'standard'—a principle or rule that guides judgment, behavior, or evaluation. The character 准 means 'accurate', 'exact', or 'to approve', suggesting reliability and correctness; 则 means 'rule', 'principle', or 'norm', often implying something authoritative or universally applicable. Together, 准则 conveys a well-established, widely accepted standard used to assess quality, ethics, or performance.

This word appears frequently in professional, academic, and institutional contexts—such as medical ethics, engineering codes, educational assessment, or corporate governance. It carries a formal, serious tone and is rarely used in casual speech. Unlike colloquial terms like 标准 (biāozhǔn), which can refer to general benchmarks, 准则 emphasizes normative guidance—especially moral, procedural, or technical standards that carry expectation or obligation.