Helped end a hunt organised in European continent (10)
I believe the answer is:
euthanasia
'helped end' is the definition.
'a hunt organised in european continent' is the wordplay.
'organised' is an anagram indicator.
'in' means one lot of letters goes inside another.
'european' becomes 'e' (abbreviation e.g. EU).
'continent' becomes 'asia' (Asia is an example).
'a'+'hunt'='ahunt'
'ahunt' is an anagram of 'uthan'.
'e'+'asia'='easia'
'uthan' inserted within 'easia' is 'EUTHANASIA'.
(Other definitions for euthanasia that I've seen before include "Mercy killing" , "Painless method of killing" .)