烟囱
yān cōng · HSK 7
chimney
🏭💨 烟 (yān, smoke) + 囱 (cōng, vent/flue) = the smoke-vent, a chimney
烟 means smoke and shows up in 烟 for cigarette/tobacco too; 囱 is an old word for a flue or vent opening. Stack them and you get the smoke-flue: 烟囱, a chimney.
烟 — fire radical 火 + 因 (cause, phonetic)
A semantic-phonetic compound: 火 ('fire') gives the meaning, while 因 supplies the sound 'yīn', close to 'yān'. Originally referring to the smoke rising from a fire, 烟 later extended to mist, vapor, and eventually tobacco and cigarettes in modern usage.