mastication vs chewing

mastication and chewing both are nouns.

Word	Noun	Adjective	Verb	Adverb
mastication	Yes	No	No	No
chewing	Yes	No	No	No

As nouns, mastication and chewing are synonyms defined as:

mastication and chewing: biting and grinding food in your mouth so it becomes soft enough to swallow

Other synonyms of mastication include chew, manduction.

mastication (noun)	chewing (noun)
biting and grinding food in your mouth so it becomes soft enough to swallow	biting and grinding food in your mouth so it becomes soft enough to swallow