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