1. devices that connect two parts of a machine or system together
Usage: mechanical/engineering
2. connections between railroad cars that allow them to be joined together
Usage: railway/transportation
3. the act or process of joining or connecting things together

Examples

• The engineer inspected all the pipe couplings for leaks.
• The train’s couplings were damaged in the accident.
• These flexible couplings reduce vibration between the motor and pump.
• The mechanic replaced the worn couplings in the drive system.
• Railroad workers must check the couplings before each departure.
• The couplings of various systems created a complex network.