aniseikonia

noun
an·​is·​ei·​ko·​nia | \ ˌa-ˌnī-ˌsī-ˈkō-nē-ə How to pronounce aniseikonia (audio) \

Definition of aniseikonia

: a defect of binocular vision in which the two retinal images of an object differ in size

Other Words from aniseikonia

aniseikonic \ ˌa-​ˌnī-​ˌsī-​ˈkä-​nik How to pronounce aniseikonic (audio) \ adjective

First Known Use of aniseikonia

1934, in the meaning defined above

History and Etymology for aniseikonia

anis- + Greek eikṓn "image" + -ia;1 — more at icon

Note: The American ophthalmologist Walter B. Lancaster (1863-1951) took credit for coining the word in an article "Aniseikonia" published jointly in the Transactions of the American Ophthalmological Society (vol. 36 [1938], pp. 227-34) and Archives of Ophthalmology (vol. 20 [1938], pp. 907-12). Though recent sources claim that he originated the word in 1932 (as Eleanore Z. Thill, "Theory and practice of spectacle correction of aniseikonia," vol. 1, chapter 47 of Duane's Ophthalmology on CD-ROM, 2006 edition), there appears to be no evidence of this contemporary with Lancaster's publications or his professional activity in the 1930's. The usual Latinization of medical terms formed from Greek elements would have resulted in anisiconia, but the coiner chose a direct transliteration from Greek.

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The first known use of aniseikonia was in 1934

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Last Updated

27 Apr 2020

Cite this Entry

“Aniseikonia.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/aniseikonia. Accessed 1 Jun. 2020.

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aniseikonia

noun
an·​is·​ei·​ko·​nia | \ ˌan-ˌī-ˌsī-ˈkō-nē-ə How to pronounce aniseikonia (audio) \

Medical Definition of aniseikonia

: a defect of binocular vision in which the two retinal images of an object differ in size

Other Words from aniseikonia

aniseikonic \ -​ˈkän-​ik How to pronounce aniseikonic (audio) \ adjective

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