A farewell maybe said out of love (5)
I believe the answer is:
adios
'a farewell' is the definition.
(adios is a kind of farewell)
'maybe said out of love' is the wordplay.
'maybe' indicates an anagram.
'out of' indicates putting letters inside (some letters on the outside of others).
'love' becomes 'o' (love means zero in tennis).
'said' is an anagram of 'adis'.
'adis' going around 'o' is 'ADIOS'.
(Other definitions for adios that I've seen before include "Goodbye, amigo" , "Goodbye (Spanish)" , "Bye-bye (amigo)" , "Adieu, arrivederci" , "Good-bye (Sp.)" .)