In Ventnor see Vikings? (5)
I believe the answer is:
norse
'vikings?' is the definition.
(I've seen this in another clue)
'in ventnor see' is the wordplay.
'in' indicates a hidden word.
'NORSE' is hidden within 'ventnor see'.
(Other definitions for norse that I've seen before include "Snore (anag)" , "Northern European" , "Old Scandinavian language" , "Old form of Norwegian" , "Relating to ancient Scandinavia" .)