Russian horse-drawn vehicle (6)
I believe the answer is:
troika
'russian horse-drawn vehicle' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for troika that I've seen before include "Russian three-horse coach" , "cart" , "Russian carriage pulled by three horses abreast" , "Threesome" , "Russian vehicle pulled by three horses" .)