freehold vs demesne

freehold and demesne both are nouns.

Word	Noun	Adjective	Verb	Adverb
freehold	Yes	No	No	No
demesne	Yes	No	No	No

As nouns, demesne is a hypernym of freehold; that is, demesne is a word with a broader meaning than freehold:

freehold: an estate held in fee simple or for life
demesne: extensive landed property (especially in the country) retained by the owner for his own use

Other hypernyms of freehold include acres, estate, land, landed estate.

freehold (noun)	demesne (noun)
tenure by which land is held in fee simple or for life	territory over which rule or control is exercised
an estate held in fee simple or for life	extensive landed property (especially in the country) retained by the owner for his own use