coupler
nounUK /ˈkʌplə/
US /ˈkʌplər/
A coupler is a thing that joins two parts together.
The train cars were linked by a strong metal coupler.
OTHER MEANINGS
2. A device that connects two railway cars.
The worker checked the coupler between the two train cars.
3. A short tube that joins two pipes or parts.
He used a coupler to connect the two garden hoses.
4. A person or thing that pairs or links things together.
The coupler matched each new student with a buddy.