This zhé reading is a noun for the edible jellyfish and appears mainly in 海蜇, a prepared dish. The general word for a living jellyfish is 水母. For the verb 'to sting' the character is read zhē.
Bottom insect radical, a pictograph of a curled crawling creature. It anchors the meaning: 蜇 is the action of stinging creatures. The 虫 base groups it with 蜂 (bee), 蝎 (scorpion), 蛇 (snake).
Top 折 supplies the sound, zhé to zhē. It shows a hand 扌 breaking something with an axe 斤, a faint semantic bonus: a sting feels like a sudden snap of pain piercing the skin. Same phonetic in 哲, 浙.
