Locust Valley lockjaw

The Mid-Atlantic accent, or Transatlantic accent, is a consciously acquired accent of English, intended to blend together the "standard" speech of both American English and British Received Pronunciation. Spoken mostly in the early twentieth century, it is not a vernacular American accent native to any location, but an affected set of speech patterns whose "chief quality was that no Americans actually spoke it unless educated to do so". The accent is, therefore, best associated with the American upper class, theater, and film industry of the 1930s and 1940s, largely taught in private independent preparatory schools especially in the American Northeast and in acting schools. The accent's overall usage sharply declined following World War II.

According to sociolinguist William Labov, "r-less pronunciation, following Received Pronunciation, was taught as a model of correct, international English by schools of speech, acting and elocution in the United States up to the end of World War II". Prior to World War II, some American elite institutions, particularly in the Northeast, cultivated a norm influenced by the "r-less" (or non-rhotic) standard English of Southern England as an international norm of English pronunciation. Early recordings of prominent Americans born in the middle of the nineteenth century provide some insight into their adoption or not of the Mid-Atlantic speaking style. President William Howard Taft, who came from an Ohio family of modest means, and inventor Thomas Edison, who grew up in Ohio and Michigan, both used natural rhotic accents. Presidents William McKinley of Ohio and Grover Cleveland of Central New York, however, clearly employed a non-rhotic, upper-class, Mid-Atlantic quality in their speeches; both even use the distinctive affectation of a "trilled" or "flapped r" at times when r is pronounced. This trill is less consistently heard in recordings of Theodore Roosevelt, McKinley's successor from an affluent district of New York City, who also used a cultivated non-rhotic Mid-Atlantic accent but with the addition of the New York accent's once-notable coil–curl merger.

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