Like Columbus, by birth (7)
I believe the answer is:
genoese
'like columbus by birth' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for genoese that I've seen before include "From the capital of the Liguria region of Italy" , "Italian port's" , "Columbus, for one" , "From an Italian port" , "people like Columbus" .)