Chuck at the boat (6)
I believe the answer is:
launch
This clue is a double definition.
'chuck' is the first definition.
(thesaurus)
'the boat' is the second definition.
(launch is a kind of boat)
'at' acts as a link.
(Other definitions for launch that I've seen before include "Inaugurate" , "Propel on course, ship or rocket" , "Boat - set in motion" , "Power-driven boat" , "Send a vessel into water" .)