"Ta-ta!,” in Tours (5)
I believe the answer is:
adieu
'ta-ta in tours' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for adieu that I've seen before include "I'm going" , "the last word in Paris" , "cheers" , "Adios, Arrivederci" , "Au revoir (to a kind friend?)" .)