Mortarboard tosser (4)
I believe the answer is:
grad
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">mortarboard tosser</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 grad that I've seen before include "University degree holder (colloq.)" , "Person with a degree (informal)" , "Ex-student" , "One who studied" .)