炸弹
zhà dàn · HSK 6
bomb
💣 zhà dàn = explode + egg — an egg that explodes
炸 means explode or deep-fry, and 弹 means ball or pellet. Together they form bomb: an explosive pellet. The dàn in 弹 is the same character used in 鸡蛋 (egg), so think of it as the exploding egg.
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.
弹 — bow 弓 + single 单 (phonetic)
Originally a pictograph of a bow with a pellet ready to launch, 弹 depicted a slingshot or pellet bow. The form was later regularized as a phono-semantic compound: 弓 (bow) gives the meaning of shooting or springing, while 单 supplies the sound. Modern senses—bullet, to pluck, to spring—all extend from this shooting/elastic-release idea.