of necessity vs inevitably

of necessity and inevitably both are adverbs.

Word	Noun	Adjective	Verb	Adverb
of necessity	No	No	No	Yes
inevitably	No	No	No	Yes

As adverbs, of necessity and inevitably are synonyms defined as:

Other synonyms of of necessity include necessarily, needs.

of necessity (adverb)	inevitably (adverb)
in such a manner as could not be otherwise	in such a manner as could not be otherwise
	by necessity