Dumbo's proboscis (5)
I believe the answer is:
trunk
'dumbo's proboscis' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for trunk that I've seen before include "boot of Cadillac?" , "on a jumbo?" , "Large luggage case" , "Main stem of tree" , "Large storage box" .)