demesne vs manor

demesne and manor both are nouns.

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

As nouns, manor is a hyponym of demesne; that is, manor 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
manor: the landed estate of a lord (including the house on it)

demesne (noun)	manor (noun)
territory over which rule or control is exercised	the mansion of a lord or wealthy person
extensive landed property (especially in the country) retained by the owner for his own use	the landed estate of a lord (including the house on it)