... fellow making people move pointlessly (and he was triumphant) (6)
I believe the answer is:
victor
'fellow making people move pointlessly and he was triumphant' is the definition.
The answer is a person as well as being a singular noun. This is suggested by the definition.
'he was triumphant' is the wordplay.
'he' becomes 'vic'.
'was triumphant' becomes 'tor' (I can't justify this - if you can you should believe this answer much more).
'vic'+'tor'='VICTOR'
Can you help me to learn more?
(Other definitions for victor that I've seen before include "Comms code for V" , "''To the . . . . . . the spoils'' (6)" , "Conqueror" , "winning player" , "Oh dear!" .)