You can play it and see, oddly, if Oslo is Norway's capital? (6)
I believe the answer is:
'you can play it' is the definition.
I can't tell whether this definition defines the answer.
'see oddly if oslo is norway's capital?' is the wordplay.
'see' becomes 'v' (Latin 'vide', used to direct a reader to a source).
'oddly' indicates alternate letters (letters in the odd-numbered positions are used).
'capital?' indicates taking the first letters (I've seen 'capital' mean this).
The first letters of 'is norways' is 'in'.
The alternating letters of 'ifoslo' are 'iol'.
'and' is the link.
Can you help me to learn more?
(Other definitions for violin that I've seen before include "An elevated fiddle" , "A stringed musical instrument, say a Stradivarius" , "Menuhin's instrument" , "Instrument with four strings" , "Bowed instrument" .)