Primarily all brave actors performing (8)
I believe the answer is:
acrobats
'primarily all brave actors performing' is the definition.
Although both the answer and 'performing' are nouns, they are not in the same form of the noun.
'primarily all brave actors performing' is the wordplay.
'primarily' indicates taking the first letters.
'performing' indicates anagramming the letters.
The initial letters of 'all brave' is 'ab'.
'ab'+'actors'='abactors'
'abactors' with letters rearranged gives 'ACROBATS'.
(Other definitions for acrobats that I've seen before include "Circus tumblers" , "Boast car (anag.)" , "Funambulists" , "They perform feats of balance" , "Top performers" .)