吸烟
xī yān · HSK 4
to smoke
🚬 吸烟 = inhale + smoke; 吸 xī = suck in, 烟 yān = smoke/tobacco
吸 xī means to inhale or suck in (mouth radical 口 + reach 及). 烟 yān means smoke or tobacco (fire radical 火 hints at burning). Together: inhale-smoke = to smoke cigarettes.
吸 — mouth radical 口 + reach 及 (phonetic)
吸 is a phono-semantic compound. The mouth radical 口 signals the meaning—an action done with the mouth—while 及 (jí) hints at the original sound. It depicts drawing air or liquid in through the mouth, giving the modern senses 'inhale, suck, absorb'.
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.