Elastic band (6)
I believe the answer is:
garter
'elastic band' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for garter that I've seen before include "Band to keep a stocking or sleeve up" , "Stocking supporter" , "Band holding up sock" , "Support for a stocking" , "- Belt; - snake; - stitch" .)