Vessel showing many the way (4)
I believe the answer is:
dhow
'vessel' is the definition.
(dhow is a kind of vessel)
'many the way' is the wordplay.
'many' becomes 'd'.
'the way' becomes 'how' (**).
'd'+'how'='DHOW'
'showing' is the link.
(Other definitions for dhow that I've seen before include "Type of boat used in the Indian ocean" , "Arabian sailing vessel" , "Arab coastal vessel" , "Arab vessel with lateen sail" , "Arabian ship" .)