‘公鸡’ literally means ‘male chicken’ — 公 (gōng) means ‘male’ or ‘public’, and here it specifies gender, while 鸡 (jī) means ‘chicken’. Together, the term refers specifically to an adult male domestic chicken, commonly known in English as a rooster or cock. Unlike the gender-neutral 鸡, which can refer to chickens of either sex, 公鸡 always indicates maleness and is used in both everyday speech and agricultural contexts.

This word appears frequently in descriptions of farm life, folklore (e.g., the rooster’s crow signaling dawn), and idioms like ‘闻鸡起舞’ (to rise at the crow of the rooster — symbolizing diligence). It’s also used contrastively with 母鸡 (mǔ jī, ‘hen’) when distinguishing sexes, and rarely appears in formal scientific writing, where terms like ‘雄性家鸡’ (xióngxìng jiā jī) may be preferred.