Like a bird in the wake of a ship (6)
I believe the answer is:
astern
'the wake of a ship' is the definition.
I can't judge whether this definition defines the answer.
'like a bird' is the wordplay.
'like' becomes 'as'.
'a bird' becomes 'tern' (tern is a kind of bird).
'as'+'tern'='ASTERN'
'in' is the link.
Can you help me to learn more?
(Other definitions for astern that I've seen before include "at the vessel's rear" , "Towards rear of a vessel" , "Towards the rear of boat" , "Aft" , "Towards the rear of a ship" .)