Use fervent to describe a person or thing that shows very strong feelings or enthusiasm. If you have a fervent desire to become an actress, you'll stop at nothing to realize your dream. The adjective fervent and the noun fervor are often associated with the feelings aroused by patriotism, religion, or a belief that you support or oppose. A near synonym for the adjective is ardent. Fervent is from Middle English, from Old French, from the Latin verb fervēre to boil, glow.