Imperial pint, maybe making a comeback (5)
I believe the answer is:
regal
'imperial' is the definition.
(I know this)
I don't understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for regal that I've seen before include "Grand and imposing" , "Magnificent, dignified" , "Kingly or queenly" , "befitting a king" , "Royal - 5 down (anag)" .)