Knight with weapon meeting fate (8)
I believe the answer is:
lancelot
'knight' is the definition.
(thesaurus)
'weapon meeting fate' is the wordplay.
'weapon' becomes 'lance' (lance is a kind of weapon).
'meeting' says to put letters next to each other.
'fate' becomes 'lot' ('lot' can be a synonym of 'fate').
'lance'+'lot'='LANCELOT'
'with' is the link.
(Other definitions for lancelot that I've seen before include "One of King Arthur's knights, lover of Guinevere" , "Knight of the Round Table and close friend of King Arthur's wife, Guinevere" , "Arthur's knight, lover of Guinevere" , "queen's lover" , "Arthurian knight, Guinevere's lover" .)