Style of building seen in Finland (or Iceland) (5)
I believe the answer is:
doric
'style of' is the definition.
'Doric' can be an answer for 'style' (I've seen this before). I'm not sure about the 'of' bit.
'seen in finland or iceland' is the wordplay.
'seen in' indicates a hidden word.
'DORIC' is hidden in the letters of 'finland or iceland'.
'building' acts as a link.
(Other definitions for doric that I've seen before include "Of the oldest and simplest form of architecture" , "Relating to a classical order of architecture" , "A classical style of architecture with fluted columns" , "One of the Greek orders of architecture" , "Style of column" .)