Large motorboat (6)
I believe the answer is:
launch
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">large motorboat</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for launch that I've seen before include "Embark" , "Initiate; a boat" , "Boat; put in the water" , "Set (a boat) afloat" , "publicity event" .)