Uniform - and its wearer? (7)
I believe the answer is:
regular
'uniform' is the definition.
(similar in meaning)
I can't explain the rest of the clue.
Can you help me to learn more?
(Other definitions for regular that I've seen before include "Symmetrically arranged" , "Happening frequently" , "Predictable" , "Recurring at short uniform intervals" , "Customary; done frequently" .)