smallholding vs demesne

smallholding and demesne both are nouns.

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

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

smallholding: a piece of land under 50 acres that is sold or let to someone for cultivation
demesne: extensive landed property (especially in the country) retained by the owner for his own use

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

smallholding (noun)	demesne (noun)
a piece of land under 50 acres that is sold or let to someone for cultivation	territory over which rule or control is exercised
	extensive landed property (especially in the country) retained by the owner for his own use