royalty vs royal house

royalty and royal house both are nouns.

Word	Noun	Adjective	Verb	Adverb
royalty	Yes	No	No	No
royal house	Yes	No	No	No

As nouns, royalty and royal house are synonyms defined as:

Other synonyms of royalty include royal family, royal line.

royalty (noun)	royal house (noun)
royal persons collectively	royal persons collectively
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