say it: en-THOO-zee-ast
enthusiast is a noun meaning "an ardent and enthusiastic supporter of some person or activity". It carries 2 recorded senses.
an ardent and enthusiastic supporter of some person or activity
a person having a strong liking for something
Forms marked · are formed by the regular rule rather than recorded in the source data. English keeps a few hundred irregulars and the rest follow the pattern, so the rule is right far more often than not — but it is a rule, and the mark says so.
Definitions, synonyms and semantic relations for enthusiast come from Princeton University’s WordNet. The pronunciation comes from the CMU Pronouncing Dictionary. Commonness is measured against a corpus of everyday English. Full sources and licences.