Definition of "common noun"

common noun

noun
plural common nouns
1. A noun that denotes any member, or all members, of a class; an ordinary noun such as "dog" or "city". In contrast, a proper noun is a single named entity such as "Socrates".
  Quotations
  The Butlers had been serving the Fowls for centuries. It had always been that way. Indeed, there were several eminent linguists of the opinion that this was how the common noun had originated.
  2001, Eoin Colfer, Artemis Fowl, page 15