炸
zhá , zhà · HSK 6
to deep fry
🍟💥 fire (火) + suddenly (乍) — flames hit fast whether frying or blasting
zhá means deep-fry, zhà means explode. Both share the idea of something meeting fierce heat all at once. The right side 乍 (zhà) doubles as a sound hint for the explosive reading.
炸 — fire radical 火 + 乍
A semantic-phonetic compound: the fire radical 火 gives the meaning (cooking with hot oil or sudden bursting by heat), while 乍 (zhà) supplies the sound. Originally meant 'to burst' or 'explode'; the cooking sense 'to deep-fry' developed from the idea of food bursting in hot oil.