Explorer and a girl he ruined (7)
I believe the answer is:
raleigh
'explorer' is the definition.
(Sir Walter Raleigh)
'a girl he ruined' is the wordplay.
'ruined' is an anagram indicator.
'a'+'girl'+'he'='agirlhe'
'agirlhe' is an anagram of 'RALEIGH'.
'and' is the link.
(Other definitions for raleigh that I've seen before include "Sir Walter, favourite of Elizabeth I" , "Sir Walter --, courtier" , "Elizabethan courtier" , "Tudor courtier" , "Elizabethan sea-dog" .)