Ruddy promising! (4)
I believe the answer is:
rosy
I believe this clue is a double definition.
'ruddy' is the first definition.
(thesaurus)
'promising' is the second definition.
('rosy' can be a synonym of 'promising')
(Other definitions for rosy that I've seen before include "Pinkish; healthy" , "Promising; hopeful" , "Hopeful; blushing" , "lady" , "Healthy-looking" .)