The word "孔乙己" is formed by taking the common surname 孔 and appending two characters from the traditional Chinese celestial stem system: 乙, the second stem, and 己, the sixth stem. This combination creates a proper name that deliberately echoes the stylized, scholarly pseudonyms used in historical China, evoking a sense of archaic formality and pedantic identity as crafted by the author Lu Xun for his character.