Worn, threadbare (6)
I believe the answer is:
shabby
This clue is a double definition.
'worn' is the first definition.
(similar in meaning)
'threadbare' is the second definition.
(I've seen this before)
(Other definitions for shabby that I've seen before include "Old and worn - mean" , "Worn and dirty; mean" , "Run down" , "Old and threadbare" , "Seedy and rundown" .)