Titles to become a weapon (8)
I believe the answer is:
stiletto
'a weapon' is the definition.
(stiletto is a kind of weapon)
'titles to become' is the wordplay.
'become' indicates anagramming the letters.
'titles'+'to'='titlesto'
'titlesto' is an anagram of 'STILETTO'.
(Other definitions for stiletto that I've seen before include "Possible cause of stabbing pains" , "Thin blade" , "Stabbing dagger or high heel" , "Narrow-bladed dagger" , "Thin high heel" .)