Uranium record held by source of wine: cunning! (7)
I believe the answer is:
vulpine
'cunning' is the definition.
(I've seen this before)
'uranium record held by source of wine' is the wordplay.
'uranium' becomes 'U' (U is the chemical symbol for uranium).
'record' becomes 'L-P' (abbreviation for long play record).
'held by' means one lot of letters goes inside another.
'source of wine' becomes 'vine' (I can't justify this - if you can you should give a lot more credence to this answer).
'u'+'lp'='ulp'
'ulp' put within 'vine' is 'VULPINE'.
Can you help me to learn more?
(Other definitions for vulpine that I've seen before include "Like a fox -- liven up (anag)" , "Being foxy" , "Resembling a fox" , "Relating to foxes" , "Characteristic of a fox" .)