Ar·​pa·​net ˈär-pə-ˌnet How to pronounce Arpanet (audio)
variants or ARPANET or less commonly ARPAnet
: an electronic communications network that was the predecessor to the Internet
What he typed could not even be sent as an e-mail, in case it crashed the ancient Arpanet system; he had to send a message to say that it could be downloaded.Michael Hart, The Economist, 24 Sept. 2011
In June 1966, Robert Taylor took over after Sutherland accepted a post at Harvard. He conceived of the ARPANET, a network that would turn computers into communication devices, not just data crunchers.Tom Harvey, Salt Lake Tribune, 19 Dec. 2009

Word History


ARPA (Advanced Research Projects Agency, a research arm of the U.S. Department of Defense) + -net, short for network entry 1 (as in earlier telnet)

First Known Use

1971, in the meaning defined above

Time Traveler
The first known use of Arpanet was in 1971

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Cite this Entry

“Arpanet.” Dictionary, Merriam-Webster, Accessed 14 Apr. 2024.

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