Broken dinghy discovered at last (6)
I believe the answer is:
ending
'last' is the definition.
(I've seen this before)
'broken dinghy discovered' is the wordplay.
'discovered' indicates the answer is hidden within the clue (remove the letters covering the answer in the clue).
'ENDING' can be found hidden inside 'broken dinghy'.
'at' acts as a link.
(Other definitions for ending that I've seen before include "Termination, conclusion" , "Last part" , "Bringing to a close" , "Closure" , "Closing down" .)