Regally include girl (3)
I believe the answer is:
gal
'girl' is the definition.
(I know that gal is a type of girl)
'regally include' is the wordplay.
'include' says the answer is hidden in the clue.
'GAL' is hidden in the letters of 'regally'.
(Other definitions for gal that I've seen before include "An American girl, cowboy vintage" , "Lass" , "miss" , "measure of acceleration?" , "US female" .)