The term 'more than enthusiastic' can be described by four different words: MAD (3 letters), RABID (5 letters), AGOG (4 letters) and FANATIC (7 letters). MAD is an acronym for 'mentally affected disorder' and is used to describe someone who is mentally unstable. RABID is an adjective that means 'fiercely enthusiastic or passionate'. AGOG is an adverb that means 'eagerly excited or enthusiastic'. Lastly, FANATIC is a noun that describes someone who is extremely devoted to a particular cause or activity. All of these words can be used to describe someone who is more than enthusiastic about something.