swiv·el 
(swĭvəl)
(swĭvəl)n.
A device that joins two parts in a way that allows one part to turn without turning the other.
v. swiv·eled, swiv·el·ing, swiv·els or swiv·elled or swiv·el·ling
v.tr.
1. To turn or rotate on a swivel or an axis.
2. To secure, fit, or support with a swivel.
v.intr.
To turn on a swivel or an axis.
[Middle English swyvel.]