Yacht races get a tar excited (7)
I believe the answer is:
regatta
'yacht races' is the definition.
(I've seen this before)
'get a tar excited' is the wordplay.
'excited' indicates an anagram.
'get'+'a'+'tar'='getatar'
'getatar' anagrammed gives 'REGATTA'.
(Other definitions for regatta that I've seen before include "Yacht-race event" , "Yachting festival" , "Boat meeting (at Henley, say)" , "Yachting or rowing event" , "Meeting for boat races" .)