Synonyms for Enthusiasm:

n.

fad, wonder, satisfaction, anticipation, delight, kick, pleasure, joie de vivre. concern, feelings. enthusiasm (noun)
exuberance, ardor, fervor, fire, ebullience.
keen interest, excitement (noun)
fervor, relish, spirit, zeal, fire, fad, activity, passion, energy, Ardency, snap, vim, heat, go, avidity, craze, glow, zest, fury, earnestness, pep, flare, impetuosity, interest, ardor, fever, mania, emotion, life, verve, vivacity, exhilaration, keenness, joy, zealousness, eagerness, feeling.
life (noun)
vim.
vigor (noun)
exuberance, vim, power, zest, relish, energy, passion, activity, fervency, animation, agility, friskiness, gusto, vigor, sprightliness, spirit, lustiness, verve, Ardency, strength, agitation, eagerness, zeal, potency, excitement, earnestness, puissance, liveliness, industriousness.

Other synonyms:

wonder, joie de vivre, binge, zealousness, crowd pleaser, escapism, anticipation, joy, change. fever, vitality, satisfaction, amusement, blast, mania, pleasure, glow. delight, kick, enjoyment, craze. life, rage. zip. go. concern
interest.
craze
fad.
fervor
heat.
liveliness
exhilaration.
sprightliness
vivacity.

Usage examples for enthusiasm

  1. He couldn't be sure of what she might do or say, but he could be certain her curiosity and enthusiasm would stir up something. – The Egyptian Cat Mystery by Harold Leland Goodwin
  2. Her manner of enthusiasm and astonishment was sincere. – Gargoyles by Ben Hecht
  3. But directly enthusiasm began to slow down. – The Desert Fiddler by William H. Hamby