folk vs gentlefolk

folk and gentlefolk both are nouns.

Word	Noun	Adjective	Verb	Adverb
folk	Yes	No	No	No
gentlefolk	Yes	No	No	No

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

folk (noun)	gentlefolk (noun)
the traditional and typically anonymous music that is an expression of the life of people in a community	people of good family and breeding and high social status
people in general (often used in the plural)
a social division of (usually preliterate) people
people descended from a common ancestor