The word 回应 is formed by combining two meaningful characters that each contribute to its overall concept. The first character, 回 (huí), carries the core idea of "to return" or "to turn back". The second character, 应 (yìng), means "to answer", "to respond", or "to correspond to". When placed together, they create a compound where the meaning of 应 is conceptually directed by 回, visually and semantically picturing an answer that is being sent back to its source, thus perfectly encapsulating the idea of a "reply" or "response".