The word 嘟噜 is formed by combining two onomatopoeic characters: 嘟 (dū), which mimics short, abrupt sounds like honks or mumbles, and 噜 (lū), which mimics continuous or rolling sounds. Together, they create a disyllabic word that imitates a continuous, mumbling, or grumbling noise, or describes something that hangs in a cluster, leveraging the repetitive sound imagery of both characters.