The word 裤子 (kùzi), meaning "pants" or "trousers", is formed by combining the core character 裤, which itself represents the concept of trousers, with the suffix 子. This suffix 子 doesn't add a separate meaning but is a very common and neutral component attached to many nouns in Chinese. Its primary function here is not to change the meaning but to create a standard, colloquial, and complete-sounding two-syllable word from the single-character root 裤, making it flow more naturally in everyday speech.