KanjiJLPT N1
Rot

rot, decay, sour

Mnemonic

Deep in the borough, someone left a massive slab of meat in an abandoned lot. Days pass. Flies swarm. The meat begins to rot, and the entire borough reeks of decay—no one can escape the putrid smell seeping into every home.
Additional thoughts
Picture the borough as a small, enclosed district where the smell of rotting meat has nowhere to dissipate. The borough traps the stench like a lid on a container, intensifying the rot.
Quick recall
Abandoned meat in the borough starts to rot, filling every street with stench.

Details

The keyword for 腐 is rot. This kanji refers to the process of decay, decomposition, or spoilage, particularly of organic matter such as food. It conveys the idea of something breaking down, becoming putrid, or losing its original integrity over time. By extension, it can also describe moral corruption or something that has become stale and useless.
On'yomi
Kun'yomi
くさ.る、-くさ.る、くさ.れる、くさ.れ、くさ.らす、くさ.す