ancestry vs folk

ancestry and folk both are nouns.

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

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

Other hyponyms of ancestry include family, family line, kinfolk, kinsfolk, phratry, sept, side, breed line.

ancestry (noun)	folk (noun)
inherited properties shared with others of your bloodline	the traditional and typically anonymous music that is an expression of the life of people in a community
the hereditary derivation of an individual	people in general (often used in the plural)
	a social division of (usually preliterate) people
	people descended from a common ancestor