Ruth is MP. Works and succeeds (8)
I believe the answer is:
triumphs
'succeeds' is the definition.
'ruth is mp works' is the wordplay.
'works' indicates an anagram (work can mean to twist or convulse).
'ruth'+'is'+'mp'='ruthismp'
'ruthismp' anagrammed gives 'TRIUMPHS'.
'and' is the link.
(Other definitions for triumphs that I've seen before include "crows when successful" , "achievements" , "Victories and conquests" .)