anonym vs nom de guerre

anonym and nom de guerre both are nouns.

Word	Noun	Adjective	Verb	Adverb
anonym	Yes	No	No	No
nom de guerre	Yes	No	No	No

As nouns, anonym and nom de guerre are synonyms defined as:

anonym and nom de guerre: a fictitious name used when the person performs a particular social role

Other synonyms of anonym include pseudonym.

anonym (noun)	nom de guerre (noun)
a fictitious name used when the person performs a particular social role	a fictitious name used when the person performs a particular social role