A 'catalyst' (cuī huà jì) is a substance that speeds up a chemical reaction without being consumed in the process. The word breaks down literally as 催 (cuī, 'to urge or accelerate'), 化 (huà, 'to transform or change'), and 剂 (jì, 'agent or substance'). Together, they convey the idea of an agent that accelerates transformation — perfectly capturing the scientific meaning. In Chinese, this term is used almost exclusively in technical, academic, or formal contexts, especially in chemistry, medicine, and engineering.

Beyond science, 催化剂 can also be used metaphorically to describe something or someone that triggers rapid change in social, economic, or personal situations — for example, a policy reform or a key person may be called a 'catalyst' for progress. However, such figurative use remains relatively formal and less common in casual speech than its literal scientific application.