kinfolk vs line of descent

kinfolk and line of descent both are nouns.

Word	Noun	Adjective	Verb	Adverb
kinfolk	Yes	No	No	No
line of descent	Yes	No	No	No

As nouns, line of descent is a hypernym of kinfolk; that is, line of descent is a word with a broader meaning than kinfolk:

Other hypernyms of kinfolk include ancestry, blood, blood line, bloodline, descent, line, lineage, origin, parentage, pedigree, stemma, stock.

kinfolk (noun)	line of descent (noun)
people descended from a common ancestor	the hereditary derivation of an individual
	the kinship relation between an individual and the individual's progenitors