Interior vs Interior Department

Interior and Interior Department both are nouns.

Word	Noun	Adjective	Verb	Adverb
Interior	Yes	No	No	No
Interior Department	Yes	No	No	No

As nouns, Interior and Interior Department are synonyms defined as:

Interior and Interior Department: the United States federal department charged with conservation and the development of natural resources; created in 1849

Other synonyms of Interior include Department of the Interior, DoI.

Interior (noun)	Interior Department (noun)
the United States federal department charged with conservation and the development of natural resources; created in 1849	the United States federal department charged with conservation and the development of natural resources; created in 1849