Necklace (6)
I believe the answer is:
choker
'necklace' is the definition.
(I know that choker is a type of necklace)
This is all the clue.
(Other definitions for choker that I've seen before include "Tight necklet - sportsman that wilts under pressure" , "Tight necklace, collar" , "Band worn around the neck" , "Close-fitting band round neck" , "A high stiff collar or tight-fitting necklace" .)