He watches sport, etc. A mish-mash (9)
I believe the answer is:
spectator
'he watches' is the definition.
The answer is a person as well as being a singular noun. This is suggested by the definition.
'sport etc a mish-mash' is the wordplay.
'sport etc a' anagrams to 'SPECTATOR'.
But, I am not sure how the anagram is indicated.
Can you help me to learn more?
(Other definitions for spectator that I've seen before include "one found at ground?" , "One attends match" , "fan" , "He attends matches" , "Looker-on" .)