Italian "Goodbye!" (4)
I believe the answer is:
ciao
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">italian goodbye</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for ciao that I've seen before include "See you later in Rome?" , "European's greeting" , "Hello and goodbye to the Italians" , "parting word" , "Italian salutation" .)