Other forms: festering, festered, festers
To fester is to grow infected, or to grow more bitter with time. A festering wound, let it fester, resentment festered.
The literal sense is a wound becoming infected and producing pus, and it is the reason wounds are cleaned rather than covered. The figurative sense is much the commoner: a grievance left unaddressed festers, which is the standard argument for dealing with problems early. Note festering, which is used of both wounds and disputes; and that fester has nothing to do with festival, despite the resemblance.
1verbinfectedTo grow infected.
“If you don't clean that cut properly, it could fester.”
2verbfesterTo grow more bitter with time.
“Anger festered inside him after he was passed over for promotion.”
fester is a worsening.
Latin fistula meant a pipe or an ulcer, and the medical sense came into English through Old French. The word for a tube became the word for a wound that will not close, which is a fairly accurate piece of anatomy.
Proto-Indo-European
*bʰeyd-
Latin
fistula
Old French
festre
Middle English
festre
English, today
fester
Middle English festre, festur, borrowed from Old French festre (cognate with Italian fistola, Occitan fistola, Spanish fístula), from Latin fistula. The verb is derived from the noun, while the “condition of something that festers” noun sense is derived from the verb. a doublet of fistula.
Etymology from Wiktionary, CC BY-SA
Practised in A Song of Ice and Fire