entries → 外遇
TSUMUGU · TOCFL C1 (est.) · 詞
外遇 word · TOCFL C1 (est.)
外遇 ＝ 外 ＋ 遇
ㄨㄞˋ ㄩˋ · wàiyù
noun — an extramarital affair; verb — to have an affair outside one's marriage

字源 FORM — what the parts do

外outside (婚姻之外)wài
遇to meet, an encounter (相遇)yù
外遇，婚姻之外的外，相遇的遇。
關 · Related
相遇xiāngyùto meet by chance — the plain 遇出軌chūguǐto go off the rails, to cheat — the same act, another image