festering vs ichor

festering and ichor both are nouns.

Word	Noun	Adjective	Verb	Adverb
festering	Yes	No	No	No
ichor	Yes	No	No	No

As nouns, festering and ichor are synonyms defined as:

Other synonyms of festering include purulence, pus, sanies, suppuration.

festering (noun)	ichor (noun)
a fluid product of inflammation	a fluid product of inflammation
(medicine) the formation of morbific matter in an abscess or a vesicle and the discharge of pus	(Greek mythology) the rarified fluid said to flow in the veins of the Gods