Step outside the pub to see the boat (7)
I believe the answer is:
pinnace
'the boat' is the definition.
(historical type of small boat)
'step outside the pub' is the wordplay.
'step' becomes 'pace' (pace is a kind of step).
'outside' is an insertion indicator (some letters go outside others).
'the pub' becomes 'inn' (an inn is a type of pub).
'pace' enclosing 'inn' is 'PINNACE'.
'to see' is the link.
(Other definitions for pinnace that I've seen before include "Ship's boat - nice nap (anag)" , "tender" , "Vessel" , "Small boat" .)