Long to drink French wine, which is heavenly (6)
I believe the answer is:
divine
'is heavenly' is the definition.
(similar in meaning)
'long to drink french wine' is the wordplay.
'long' becomes 'die' (to long for or to die for something is to crave it).
'to drink' indicates putting letters inside.
'french wine' becomes 'vin' ('wine' in French).
'die' enclosing 'vin' is 'DIVINE'.
'which' is the link.
(Other definitions for divine that I've seen before include "Sacred; excellent" , "Godly or celestial" , "Apprehend" , "'To err is human, to forgive . . . . . .'" , "Predict" .)