We'd say "Ahoy!" in our phones today if Alexander Graham Bell had had his way. That's the telephone greeting its inventor proposed. Thomas Edison disagreed, though. He preferred the more formal, but then little-used "hello." ("Halloo" was the more familiar greeting.) Edison prevailed, and "hello" made its debut in Merriam-Webster's Collegiate Dictionary of 1898.
Source: John Morse, publisher of Merriam-Webster's Collegiate Dictionary, quoted in the Ft. Lauderdale (Fla.) Sun-Sentinel, Oct. 26, 1999.
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