demesne vs freehold

demesne and freehold both are nouns.

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

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

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

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