Cricket, maybe, is mega-excited (4)
I believe the answer is:
game
'cricket' is the definition.
(thesaurus)
'is mega-excited' is the wordplay.
'excited' is an anagram indicator.
'mega' anagrammed gives 'GAME'.
'maybe' acts as a link.
(Other definitions for game that I've seen before include "Food from wild animals" , "Up for it; gamble" , "Animal hunted for food or sport" , "Willing; plucky" , "Final declaration of tennis result - . . . ., set and match" .)