Word.ws English Dictionary

Disease X

Disease X proper noun: a hypothetical unknown pathogen that could cause a future epidemic.

Proper noun

Disease X

  1. (neologism) A hypothetical unknown pathogen that could cause a future epidemic.

Origin of Disease X

Introduced as a placeholder name by the World Health Organization in February 2018.

Questions about Disease X

What does Disease X mean?
Disease X means a hypothetical unknown pathogen that could cause a future epidemic.
What part of speech is Disease X?
Disease X is a proper noun.

Words near Disease X in the dictionary

  1. disease boats
  2. disease enhancement
  3. disease enhancements
  4. disease mongering
  5. disease of despair
  6. Disease X
  7. disease-free
  8. disease-modifying
  9. disease-ridden
  10. diseased
  11. diseasedly

Source and license

Adapted from Wiktionary: Disease X (page history and authors). Text available under the Creative Commons Attribution-ShareAlike 4.0 license. Word.ws reformatted the entry and added links. Wiktionary data of 2026-09-02.

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Cite this entry: “Disease X.” Word.ws, https://word.ws/disease_x. Based on Wiktionary, CC BY-SA 4.0.