Noah Webster's New International Dictionary of the English Language

1. (n.) Inspiration as if by a divine or superhuman power; ecstasy; hence, a conceit of divine possession and revelation, or of being directly subject to some divine impulse.

2. (n.) A state of impassioned emotion; transport; elevation of fancy; exaltation of soul; as, the poetry of enthusiasm.

3. (n.) Enkindled and kindling fervor of soul; strong excitement of feeling on behalf of a cause or a subject; ardent and imaginative zeal or interest; as, he engaged in his profession with enthusiasm.

4. (n.) Lively manifestation of joy or zeal.