Went "Ptui!" (4)
I believe the answer is:
spat
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">went ptui</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for spat that I've seen before include "Quarrel; oyster spawn" , "Minor conflict" , "Small row between Pats" , "Unimportant quarrel between Pats" , "Gestured with contempt" .)