Oxen connector (4)
I believe the answer is:
yoke
'oxen connector' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for yoke that I've seen before include "couple" , "Burdensome restraint or oppression" , "wooden frame" , "Something burdensome and oppressive" , "Oxen harness" .)