Make glad (6)
I believe the answer is:
please
'make glad' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for please that I've seen before include "Polite request - make someone happy" , "Satisfy aesthetically" , "Be good enough to" , "See pal (anag) -- charm" , "Give pleasure to (someone)" .)