en ‧ thu ‧ si ‧ ast /ɪnˈθjuːziæst $ ɪnˈθuː-/ BrE AmE noun [countable]
[ Word Family: noun : ↑ enthusiasm , ↑ enthusiast ; verb : ↑ enthuse ; adverb : ↑ enthusiastically ≠ UNENTHUSIASTICALLY ; adjective : ↑ enthusiastic ≠ UNENTHUSIASTIC ]
someone who is very interested in a particular activity or subject
baseball/outdoors/sailing etc enthusiast
a keep-fit enthusiast
enthusiast for
an enthusiast for the latest management thinking