干渉
かんしょう · kanshou · JLPT N1 · noun
intervention
🌊 干 (intrude) + 渉 (wade across) = wading into someone else's business
渉 originally meant wading across a stream, so 干渉 is stepping into the water of another person's affairs. It means interference in general or intervention in someone else's matters.
干 — pictograph of a forked weapon/shield
干 originally depicted a forked wooden weapon or shield used in ancient warfare, giving the early sense of 'to offend' or 'to oppose.' Over time it took on extended meanings like 'to concern' and 'trunk/stem.' In modern simplified Chinese it also absorbed 乾 (dry) and 幹 (to do; trunk), so one character now covers several unrelated words.