festering

(noun) (medicine) the formation of morbific matter in an abscess or a vesicle and the discharge of pus. Synonyms: suppuration, maturation.

(noun) a fluid product of inflammation. Synonyms: pus, purulence, suppuration, ichor, sanies.

(verb) ripen and generate pus. Synonyms: fester, maturate, suppurate. Example: "Her wounds are festering."