Great regal style (5)
I believe the answer is:
large
'great' is the definition.
(I know that great can be written as large)
'regal style' is the wordplay.
'style' indicates anagramming the letters (style can mean to shape or design).
'regal' is an anagram of 'LARGE'.
(Other definitions for large that I've seen before include "Tall" , "Ample" , "Lager (anag.)" , "substantial" , "Above average in size, number, etc." .)