A shunt in general is a sort of relief valve, or diverter. See:

• shunt (medical)
• shunt (electrical)

See also: shunter (railway locomotive)

In railway operations, "shunting" involves the process of sorting items of rolling stock into complete train sets or consists. The American equivalent is "switching". See:

• shunt (railway operations)

• Shunt is also a British motor racing term, indicating that a vehicle has spun out or has otherwise left the approved course.

Shunt | Shunt