Douglas Harper's Etymology Dictionary
1934, a ghost word printed in "Webster's New International Dictionary" and defined as a noun used by physicists and chemists, meaning "density." In sorting out and separating abbreviations from words in preparing the dictionary's second edition, a card marked "D or d" meaning "density" somehow migrated from the "abbreviations" stack to the "words" stack. The "D or d" entry ended up being typeset as a word, dord, and defined as a synonym for density. The mistake was discovered in 1939.
The word dord is a notable error in lexicography, an accidental creation, or ghost word, of the G. and C. Merriam Company's staff in the second (1934) edition of its New International Dictionary, in which the term is defined as "density".
Philip Babcock Gove, an editor at Merriam-Webster who became editor-in-chief of Webster's Third New International Dictionary, wrote a letter to the journal American Speech, fifteen years after the error was caught, in which he explained why "dord" was included in that dictionary.
On July 31, 1931, Austin M. Patterson, Webster's chemistry editor, sent in a slip reading "D or d, cont./density." This was intended to add " density" to the existing list of words that the letter "D" can abbreviate. The slip somehow went astray, and the phrase "D or d" was misinterpreted as a single, run-together word: Dord (This was a plausible mistake because headwords on slips were typed with spaces between the letters, making "D or d" look very much like "D o r d"). A new slip was prepared for the printer and a part of speech assigned along with a pronunciation. The would-be word got past proofreaders and appeared on page 771 of the dictionary around 1934.
On February 28, 1939, an editor noticed "dord" lacked an etymology and investigated. Soon an order was sent to the printer marked "plate change/imperative/urgent". In 1940, bound books began appearing without the ghost word but with a new abbreviation (although inspection of printed copies well into the 1940s show "dord" still present). The non-word "dord" was excised, and the definition of the adjacent entry " Doré furnace" was expanded from "A furnace for refining dore bullion" to "a furnace in which dore bullion is refined" to close up the space. Gove wrote that this was "probably too bad, for why shouldn't dord mean 'density'?" The entry "dord" was not removed until 1947.
The dord is a bronze horn native to Ireland, with excavated examples dating back as far as 1000 BC, during the Bronze Age. 104 original dords are known to exist, although replicas have been built since the late 20th century.
Though the musical tradition of the dord has been lost, modern performers such as Rolf Harris and Alan Dargin believe it was played in a manner similar to the didgeridoo and apply that technique (including circular breathing and shifts in timbre) accordingly for modern fusion music. The Irish musician Simon O'Dwyer recreates historically accurate dord.