Royal in group for meal (6)
I believe the answer is:
brunch
'for meal' is the definition.
(brunch is a kind of meal)
'royal in group' is the wordplay.
'royal' becomes 'r' (abbreviation).
'in' means one lot of letters goes inside another.
'group' becomes 'bunch'.
'r' inserted inside 'bunch' is 'BRUNCH'.
(Other definitions for brunch that I've seen before include "Late morning repast" , "Mid-morning meal" , "Combination breakfast and lunch" , "Late morning meal" , "Combined breakfast and lunch" .)