From Longman Dictionary of Contemporary Englishproper nounˌproper ˈnoun (also proper name especially British English) noun [countable] SLGNAME OF A THINGa noun such as ‘James’, ‘New York’, or ‘China’ that is the name of one particular thing and is written with a capital letter → noun
Examples from the Corpus
proper noun• Answer: a. Why: Use hyphens with a prefix and a proper noun.• A text for students devoted seven pages to the use of a capital letter to indicate a proper noun.• There are 60 grammatical categories specified within this lexicon indicating such properties as transitive verb, plural noun, proper noun etc. 