Farewell from a French deity (5)
I believe the answer is:
adieu
'farewell' is the definition.
(adieu is a kind of farewell)
'a french deity' is the wordplay.
'french deity' becomes 'dieu' (I can't justify this - if you can you should give a lot more credence to this answer).
'a'+'dieu'='ADIEU'
'from' acts as a link.
Can you help me to learn more?
(Other definitions for adieu that I've seen before include "Farewell (French)" , "Goodbye to the French" , "Farewell, adios" , "A valediction" , "farewell message" .)