回答
かいとう · kaitou · JLPT N2 · noun
answer
💬 回 = return or turn back, 答 = answer: an answer that travels back to whoever asked
回 means turning around or returning, and 答 is the answer itself. Together they describe a reply sent back the way it came to the person who asked.
回 — enclosure 囗 + smaller 囗 inside
回 is a pictograph of a swirling whirlpool or coiled spiral, shown as nested squares in modern form. The original meaning was 'to revolve' or 'turn around,' which extended to 'return' and 'a time/occurrence.' It also appears as a phonetic in characters like 茴 and 廻.
答 — bamboo radical 竹 + 合 (combine)
Originally written with the bamboo radical because answers were inscribed on bamboo slips. The phonetic 合 ('to join, match') gives both the sound and the sense of a reply 'matching' a question. Over time 答 came to mean 'answer' or 'respond' generally.