蜡烛
làzhú · HSK 7
candle
🕯️ 蜡 = wax (note the 虫 bug radical, from beeswax) + 烛 = torch with 火 fire radical
蜡烛 stacks wax onto fire: 蜡 carries the 虫 insect radical because wax once came from bees, and 烛 carries the 火 fire radical for the burning flame. Wax + fire = candle.
蜡 — insect radical 虫 + 昔 (xī, phonetic)
蜡 is a semantic-phonetic compound. The 虫 radical signals a connection to insects, originally referring to wax produced by bees and other insects. 昔 supplies the sound. Over time the meaning broadened to wax in general, including candles.