KanjiJLPT N1
Fertilizer

fertilizer, get fat, fertile, manure, pamper

Mnemonic

Under the moon, a cobra slithers through your garden, leaving a trail of shimmering venom that seeps into the soil like fertilizer. Wherever the cobra passes, the earth swells rich and fat—crops bulging plump under the moonlight, fed by the serpent's nourishing gift.
Additional thoughts
Picture the cobra's venom glowing silver in moonlight as it soaks into dark soil, making everything grow absurdly thick and plump. The moon watches over this strange enrichment ritual each night.
Quick recall
A cobra slithers under the moon, its venom enriching the soil like potent fertilizer.

Details

The keyword for 肥 is fertilizer. This kanji conveys the idea of enriching or fattening, encompassing both the notion of making soil rich through fertilizer and the concept of becoming plump or fat. It carries the dual sense of nourishment—whether applied to land to make it fertile or to a body that grows stout from abundant feeding. By extension, it can also suggest prosperity or enrichment in a broader sense.
On'yomi
Kun'yomi
こ.える、こえ、こ.やす、こ.やし、ふと.る