people vs masses

people and masses both are nouns.

Word	Noun	Adjective	Verb	Adverb
people	Yes	No	Yes	No
masses	Yes	No	No	No

As nouns, people and masses are synonyms defined as:

Other synonyms of people include hoi polloi, mass, multitude, the great unwashed.

people (noun)	masses (noun)
(plural) any group of human beings (men or women or children) collectively	the common people generally
the body of citizens of a state or country
members of a family line
the common people generally

people (verb)	masses (verb)
fill with people
furnish with people