Being zealous means to be passionately devoted to something, and there are many different words that can be used to express this level of enthusiasm. Some synonyms for "be zealous" might include being enthusiastic, fervent, passionate, fervid, eager, ardent, or even fanatical about something. These words all imply a deep level of commitment to a particular cause, idea, or hobby. They suggest that the person is willing to go to great lengths to achieve their goals and pursue their passions. No matter which word is chosen, it is clear that being zealous is a powerful trait that can inspire others and lead to great success.