Part of Scandinavia grateful for potent drug (6)
I believe the answer is:
viagra
'potent drug' is the definition.
(viagra is a drug)
'part of scandinavia grateful for' is the wordplay.
'part of' indicates a hidden word.
'VIAGRA' is hidden in the letters of 'scandinavia grateful for'.
(Other definitions for viagra that I've seen before include "Drug aiding one's sex life" , "Drug treating impotence" , "Sildenafil citrate" , "Drug to improve potency" , "Promoter of the other" .)