Learn the meaning and correct usage of " enthusiastic ". Our guide provides clear grammar rules and real-world examples from authoritative sources to help you write with confidence. The meaning of ENTHUSIASTIC is filled with or marked by enthusiasm. How to use enthusiastic in a sentence. Enthusiastic appreciation for something is more than just liking it — it's loving it. You're an enthusiastic fan of Italian food if you not only like it, you can't live without it. Enthusiastic definition: full of or characterized by enthusiasm; ardent.. See examples of ENTHUSIASTIC used in a sentence.