The word 伴郎 is formed by combining two characters: 伴 (bàn), which means "companion" or "to accompany", and 郎 (láng), a traditional term for a young man or, in this context, the groom. Together, they create a direct and descriptive compound meaning "the groom's male companion", specifically referring to the role of the best man in a wedding, whose primary function is to accompany and assist the groom.