Frequency (pínlǜ) is a noun referring to how often something occurs within a given time period. It combines two characters: 频 (pín), meaning 'frequent' or 'repeated', and 率 (lǜ), meaning 'rate' or 'ratio'. Together, they literally mean 'rate of occurrence' — a concept used widely in science, engineering, statistics, and everyday life.

In Chinese, pínlǜ appears in contexts like sound waves (e.g., audio frequency), radio transmission (radio frequency), public health (infection frequency), and daily habits (e.g., how often someone exercises). It’s often paired with measure words like 次 (cì, 'times') or units like 赫兹 (hèzī, 'hertz'). Unlike English, Chinese doesn’t use pínlǜ as a verb; it functions strictly as a countable or uncountable noun depending on context, and typically follows quantifiers or modifiers like 高 (gāo, 'high') or 低 (dī, 'low').