Type of necktie (5)
I believe the answer is:
ascot
'type of necktie' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for ascot that I've seen before include "track" , "somewhere in Berks" , "Racecourse, home to the Gold Cup since 1807" , "Berkshire race course" , "racing centre" .)