purulence vs pus

purulence and pus both are nouns.

Word	Noun	Adjective	Verb	Adverb
purulence	Yes	No	No	No
pus	Yes	No	No	No

As nouns, purulence and pus are synonyms defined as:

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

purulence (noun)	pus (noun)
a fluid product of inflammation	a fluid product of inflammation
symptom of being purulent (containing or forming pus)