Westbound sailor taking in coastal country's capital (6)
I believe the answer is:
bogota
'capital' is the definition.
(Bogota is an example)
'westbound sailor taking in coastal country's' is the wordplay.
'westbound' says the letters should be written backwards (letters written from right to left).
'sailor' becomes 'ab' (abbreviation for able seaman).
'taking in' means one lot of letters goes inside another.
'coastal country' becomes 'togo'.
'ab' enclosing 'togo' is 'atogob'.
'atogob' reversed gives 'BOGOTA'.
(Other definitions for bogota that I've seen before include "Capital city of Colombia" , "Colombian capital" , "Columbian capital" , "Colombian city" , "Andean city" .)