Fragment of glass (5)
I believe the answer is:
shard
'fragment of glass' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for shard that I've seen before include "Piece of broken ceramic - London skyscraper" , "Go well with; attire" , "Scrap of pottery" , "remnant after break-up" , "Sliver of glass, etc" .)