Have a good trip! (3,6)
I believe the answer is:
bon voyage
'have a good trip' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for bon voyage that I've seen before include "travel well!" , "Have a good trip - on the briny" , "Have a good journey - at sea" , "Have a nice cruise, monsieur" .)