Tatty broken dagger (6)
I believe the answer is:
ragged
'tatty' is the definition.
('ragged' can be a synonym of 'tatty')
'broken dagger' is the wordplay.
'broken' indicates anagramming the letters.
'dagger' is an anagram of 'RAGGED'.
(Other definitions for ragged that I've seen before include "Scruffy" , "Unkempt" , "Tattered and torn" , "Dressed in torn clothes" , "Describes worn or torn clothes" .)