TELNET /tel'net/ vt. (also commonly lowercased as `telnet') To communicate with another Internet host using the TELNET ({RFC} 854) protocol (usually using a program of the same name). TOPS-10 people used the word IMPCOM, since that was the program name for them. Sometimes abbreviated to TN /T-N/. "I usually TN over to SAIL just to read the AP News."