Definition
A single-conductor electrical connector with a cylindrical metal tip that has flexible spring-loaded leaves bulging outward along its sides, giving it a banana-like shape. The springy leaves grip the inside of a matching socket to make a secure electrical contact while still allowing easy insertion and removal by hand.
Plain English
A plug shaped like a small banana, with springy sides that press against the inside of a socket to hold it in place and carry an electrical signal.
Context Anchor
Seen during aircraft electrical troubleshooting, especially when connecting meters, power supplies, or test leads to equipment on the bench or in the aircraft.
Derivation
Named for its shape: the springy metal leaves on the side of the plug bulge outward like a banana, which is how it both looks and grips inside the socket.
Why Pilots Care
Provides quick, secure temporary connections when checking or calibrating aircraft electrical systems.
Analogy
Like the springy probes on a handheld multimeter.
Intuition Check
“Banana” does not mean the plug is flexible, soft, or made for aviation only. It refers to the plug’s shape and spring-contact design.
Example Sentence 1
The technician inserted the banana plug into the test jack to check continuity in the landing light circuit.
Example Sentence 2
Banana plugs let the mechanic swap leads quickly while checking voltage at the battery bus.