ISBN (identifier) Stigler's law of eponymy List of religious titles and styles
The mythological Greek hero Orion is the eponym of the constellation Orion, shown here, and thus indirectly of the Orion spacecraft.[1]

An eponym is a person, place, or thing after whom or which someone or something is, or is believed to be, named. The adjectives derived from eponym include eponymous and eponymic.

Word usage

The word is used in different ways. In the most frequently cited meaning, an eponym[2][3] is a person, place, or thing after whom or after which something is named, or believed to be named. In this way, Elizabeth I of England is the eponym of the Elizabethan era. If Henry Ford is referred to as "the eponymous founder of the Ford Motor Company", either Henry Ford himself, or his name "Ford" could be called the eponym. Conversely, the name of the new thing can be called the eponym, and, especially in the recorded-music industry, eponymous is used to mean "named after its central character or creator".[4][5][6][7]


Periods have often been named after a ruler or other influential figure:


Other eponyms

Orthographic conventions

Capitalized versus lowercase

For examples, see the comparison table below.

Genitive versus attributive

National varieties of English

Comparison table of eponym orthographic styling

Prevalent dictionary styling today Stylings that defy prevalent dictionary styling Comments
Addison disease[27] *Addison Disease
*addison disease
Allemann syndrome[27] *Allemann Syndrome
*allemann syndrome
cesarean [only][27]
cesarean also cesarian [but no cap variant][15]
cesarean, "often capitalized" or caesarean also cesarian or caesarian[28]
  More information on this word's orthographic variants is at Wiktionary: caesarean section.
darwinian [only][27]
darwinism [only][27]
Darwinian [only][15][16]
Darwinism [only][15][16]
Darwinist [only][15][16]
diesel (n/adj/vi) [no cap variant][15][16]
and also
diesel engine[15][16]
dieselize, dieselization[15]
*Diesel engine
*Dieselize, Dieselization
draconian often Draconian[15]
eustachian [only][27]
eustachian often Eustachian[15]
eustachian tube [only][27]
eustachian tube often Eustachian tube[15]
eustachian tube or Eustachian tube[16]
*Eustachian Tube  
fallopian [only][27]
fallopian often Fallopian[15]
fallopian tube [only][27]
fallopian tube often Fallopian tube[15]
fallopian tube also Fallopian tube[16]
*Fallopian Tube  
Marxism [only][15][16]
Marxist [only][15][16]
mendelian [only][27] or Mendelian [only][15]
mendelian inheritance [only][27] or Mendelian inheritance [only][15] 
Mendel's laws[15][27]
*Mendelian Inheritance  
Newtonian [only][15][16] *newtonian  
parkinsonism [only][15][27]
parkinsonian [only][15][27]
parkinsonian tremor[27]
Parkinson disease [only][27]
Parkinson's disease [only][15]
*Parkinsonian tremor
*Parkinsonian Tremor
*Parkinson Disease
*Parkinson's Disease
quixotic [only][15][16] *Quixotic  
Roman numerals[16]
roman numerals[15]
  AMA Manual of Style lowercases the terms roman numerals and arabic numerals. MWCD enters the numeral sense under the headword Roman but with the note "not cap" on the numeral sense.[15]

Lists of eponyms

By person's name

By category

See also


  1. ^ "Orion Spacecraft - Nasa Orion Spacecraft". aerospaceguide.net.
  2. ^ (ancient Greek ἐπώνυμος (a.) given as a name, (b.) giving one's name to a thing or person, ἐπί upon + ὄνομα, Aeolic ὄνυμα name)
  3. ^ "eponym, n. : Oxford English Dictionary". OED Online. 2019-10-26. Archived from the original on 2019-10-26. Retrieved 2019-10-27.
  4. ^ "eponym". Dictionary.com. Dictionary.com LLC. Retrieved 30 December 2014.
  5. ^ "eponym". Merriam-Webster Online Dictionary. Merriam-Webster. Retrieved 30 December 2014.
  6. ^ "eponymous". Dictionary.com. Dictionary.com LLC. Retrieved 30 December 2014.
  7. ^ "eponymous". Merriam-Webster Online Dictionary. Merriam-Webster. Retrieved 30 December 2014.
  8. ^ Bayer Co. v. United Drug Co., 272 F. 505 (S.D.N.Y. 1921), Berkman Center for Internet & Society at Harvard University, accessed March 25th, 2011
  9. ^ Harper, Douglas. "heroin". Online Etymology Dictionary.
  10. ^ King-Seeley Thermos Co. v. Aladdin Indus., Inc., 321 F.2d 577 (2d Cir. 1963); see also this PDF Archived 2006-02-09 at the Wayback Machine
  11. ^ Beolens, Bo; Watkins, Michael; Grayson, Michael (2014). The Eponym Dictionary of Birds. Bloomsbury Publishing. ISBN 978-1472905741.
  12. ^ Hämäläinen, Matti (2015). "Catalogue of individuals commemorated in the scientific names of extant dragonflies, including lists of all available eponymous species-group and genus-group names" (PDF). International Dragonfly Fund (IDF) - Report. 80: 1–168. ISSN 1435-3393. Retrieved 18 September 2020.
  13. ^ a b c Waddingham, Anne (28 August 2014). New Hart's Rules: The Oxford Style Guide. OUP Oxford. p. 105. ISBN 978-0199570027.
  14. ^ Marthus-Adden Zimboiant (2013-08-05). No Grammar Tears 1. pp. 256–257. ISBN 9781491800751.
  15. ^ a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab ac Merriam-Webster (1993), Merriam-Webster's Collegiate Dictionary (10th ed.), Springfield, Massachusetts, USA: Merriam-Webster, ISBN 978-0-87779-707-4
  16. ^ a b c d e f g h i j k l m n o Houghton Mifflin (2000), The American Heritage Dictionary of the English Language (4th ed.), Boston and New York: Houghton Mifflin, ISBN 978-0-395-82517-4
  17. ^ University of Chicago (1993). The Chicago Manual of Style (14th ed.). Chicago: University of Chicago Press. § 7.49, pp. 253–254. ISBN 0-226-10389-7.
  18. ^ Lorraine Villemaire, Doreen Oberg (29 December 2005). Grammar and Writing Skills for the Health Professional (2nd Revised ed.). Delmar Cengage Learning. p. 167. ISBN 978-1401873745.CS1 maint: uses authors parameter (link)
  19. ^ Centers for Disease Control and Prevention. Emerging Infectious Diseases Journal Style Guide. Preferred Usage
  20. ^ Lisa Brown, Julie M. Wolf, Rafael Prados-Rosales & Arturo Casadevall (2015). "Through the wall: extracellular vesicles in Gram-positive bacteria, mycobacteria and fungi". Nature Reviews Microbiology. 13 (10): 620–630. doi:10.1038/nrmicro3480. PMC 4860279. PMID 26324094.CS1 maint: uses authors parameter (link)
  21. ^ Kristen L. Mueller (12 June 2015). "Detecting Gram-negative bacteria". Science. 348 (6240): 1218. doi:10.1126/science.348.6240.1218-o.
  22. ^ "Gram-positive". Dictionary.com.
  23. ^ "Newtonian". Merriam-Wester.
  24. ^ "New·ton". The American Heritage Dictionary.
  25. ^ Iverson, Cheryl (editor) (2007), AMA Manual of Style (10 ed.), Oxford, England: Oxford University Press, ISBN 978-0-19-517633-9CS1 maint: extra text: authors list (link), chapter 16: Eponyms.
  26. ^ Medical Subject Headings (MeSH) of the United States National Library of Medicine (NLM) uses "cesarean section", while the also US-published Saunders Comprehensive Veterinary Dictionary uses "caesarean". The online versions of the Merriam-Webster Dictionary and American Heritage Dictionary list "cesarean" first and other spellings as "variants", an etymologically anhistorical position.
  27. ^ a b c d e f g h i j k l m n o p Elsevier (2007), Dorland's Illustrated Medical Dictionary (31st ed.), Philadelphia: Elsevier, ISBN 978-1-4160-2364-7
  28. ^ Merriam-Webster (2003), Merriam-Webster's Collegiate Dictionary (11th ed.), Springfield, Massachusetts, USA: Merriam-Webster, ISBN 978-0-87779-809-5