化肥
huà féi · HSK 7
fertilizer
🌱 化 chemical + 肥 fat/fertile = the chemical that fattens soil = fertilizer
肥 means fat or fertile (the moon radical 月 for flesh), so 化肥 is literally chemical-fertile-stuff. Sound hook: huà féi rhymes with way-fay, the way to make fields fat.
化 — person 亻 + spoon/upside-down person 匕
化 is an associative compound showing a standing person 亻 next to 匕, originally a depiction of a person turned upside-down. Together they suggest a figure transforming from one state to another, giving the core meaning 'change' or 'transform'. The character later extended to senses like 'convert', 'influence', and the noun suffix '-ization'.
肥 — flesh radical 月(肉) + 巴
Originally written with 肉 (flesh/meat) on the left and a phonetic-like component on the right, 肥 depicted abundant flesh on a body, hence 'fat' or 'plump'. Over time the 肉 radical was simplified to 月 in left-side position. The meaning extended from animal fatness to 'fertile' (as in rich soil) and 'fertilizer'.