Carry out a Parisian during test (5)
I believe the answer is:
mount
'carry out' is the definition.
'a parisian during test' is the wordplay.
'a parisian' becomes 'un'.
'during' is an insertion indicator.
'test' becomes 'mot'.
'un' going inside 'mot' is 'MOUNT'.
(Other definitions for mount that I've seen before include "The height" , "Steed" , "stage" , "Fix onto a backing" , "Get on - horse" .)