He is held back by more audacious viewer (8)
I believe the answer is:
beholder
'viewer' is the definition.
(thesaurus)
'he is held back by more audacious' is the wordplay.
I cannot really understand how this works, but
'he' could be 'der' and 'der' is located in the answer.
'is' could be 'be' and 'be' is found in the answer.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for beholder that I've seen before include "Observer" , "Onlooker" , "Some looker" , "One who observes" , "Witness" .)