Limits RegistryPUBLIC RECORD
Limits RegistryPneumonoultramicroscopicsilicovolcanoconiosis, a 45-letter term for a lung disease caused by inhaling very fine silicate or quartz dust, is the longest word in major English dictionaries including the Oxford English Dictionary. It was coined in 1935 by Everett M. Smith, president of the National Puzzlers' League, as a deliberately long word.
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Pneumonoultramicroscopicsilicovolcanoconiosis, a 45-letter term for a lung disease caused by inhaling very fine silicate or quartz dust, is the longest word in major English dictionaries including the Oxford English Dictionary. It was coined in 1935 by Everett M. Smith, president of the National Puzzlers' League, as a deliberately long word.
The greatest number of letters in a word with an entry in a major general-purpose English dictionary such as the Oxford English Dictionary.
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1 accepted Claim, with 1 linked evidence records.
Permanent ID limitsregistry.com/limits/LR-LONGEST-WORD-IN-MAJOR-ENGLISH-DICTIONARY
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Limits Registry. LR-LONGEST-WORD-IN-MAJOR-ENGLISH-DICTIONARY. Longest word in a major English dictionary. 2026.