society vs frat

society and frat both are nouns.

Word	Noun	Adjective	Verb	Adverb
society	Yes	No	No	No
frat	Yes	No	No	No

As nouns, frat is a hyponym of society; that is, frat is a word with a more specific, narrower meaning than society:

society (noun)	frat (noun)
an extended social group having a distinctive cultural and economic organization	a social club for male undergraduates
a formal association of people with similar interests
the fashionable elite
the state of being with someone