Mythical female sailor went first (6)
I believe the answer is:
fabled
'mythical' is the definition.
(thesaurus)
'female sailor went first' is the wordplay.
'female' becomes 'f' (abbreviation).
'sailor' becomes 'ab' (abbreviation for able seaman).
'went first' becomes 'led'.
'f'+'ab'+'led'='FABLED'
(Other definitions for fabled that I've seen before include "noted" , "Well-known" , "Famous; imaginary" , "Legendary, mythical" , "Enshrined in ancient stories or legends" .)