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proper adjective (plural proper adjectives)

  1. (grammar) An adjective derived from a proper noun, such as British derived from Britain.
    • 1859, William Harvey Wells, A Grammar of the English Language: For the Use of Schools
      These two general classes of adjectives may also be divided into several others, of which the following are the most important: — 1. A proper adjective is one that is derived from a proper name; as, American . . .