noun
Refers to the worm-like larva of flies, often found on decaying matter. Can be used literally or figuratively to describe something repulsive.
生ゴミにうじがわいていた。
Maggots were breeding in the kitchen waste.
腐った肉にはうじがたかる。
Maggots swarm on rotten meat.
The origin is uncertain; it is a native Japanese word (和語) with no clear kanji etymology. The kanji 蛆 is a Chinese character used for its meaning, not phonetic origin.