City of Scandinavia, large one principally (4)
I believe the answer is:
oslo
'city' is the definition.
(Oslo is an example)
'of scandinavia large one principally' is the wordplay.
'principally' says to take the initial letters.
The initial letters of 'of scandinavia large one' is 'OSLO'.
(Other definitions for oslo that I've seen before include "Capital often frozen" , "Location" , "Solo in Norway?" , "Nordic capital" , "Capital of Norway" .)