One who tries out a canopy (6)
I believe the answer is:
tester
'canopy' is the definition.
(I know that tester is a type of canopy)
I don't understand the remainder of the clue.
Can you help me to learn more?
(Other definitions for tester that I've seen before include "One who analyses a bed canopy" , "A canopy over a large bed, or an examiner" , "Person examining" , "Kind of examiner or bed canopy" , "One sampling; four-poster bed canopy" .)