from Wiktionary, Creative Commons Attribution/Share-Alike License
- proper n. The puppet Kermit the Frog, host of The Muppet Show and a frequent character in Sesame Street, originally performed by creator Jim Henson.
- proper n. An asynchronous file transfer protocol, often used for communication between different types of minicomputer or mainframe.
Computing sense named after the Sesame Street character, but later provided with a backronym ("KL10 Error-Free Reciprocal Microprocessor Interchange over TTY"). (Wiktionary)