fester
[verb]
Synonyms:
- decay, putrefy, suppurate, ulcerate
- intensify, aggravate, smoulder

[TahlilGaran] English Synonym Dictionary ▲

fes‧ter /ˈfestə $ -ər/ verb [intransitive]
[Date: 1300-1400; Language: Old French; Origin: festre 'sore hole in flesh', from Latin fistula]

1. if an unpleasant feeling or problem festers, it gets worse because it has not been dealt with:
The dispute can be traced back to resentments which have festered for centuries.

2. if a wound festers, it becomes infected:
festering sores

3. if rubbish or dirty objects fester, they decay and smell bad

[TahlilGaran] Dictionary of Contemporary English ▲