Meanings
plural Ishihara tests
- A test for red-green color blindness, using a number of colored plates (Ishihara plates), each of which contains a circle of dots of various colors and sizes. Depending on the person's vision, certain dots within the pattern will appear to form recognizable numbers or shapes.
In order to check on a clinically derived impression of a greater incidence of color-blindness among psychotic patients, the Ishihara Test (5) was given to a group of patients at the Worcester State Hospital.
1935 May 28, Mary S. Millard, David Shakow, “A NOTE ON COLOR-BLINDNESS IN SOME PSYCHOTIC GROUPS”, in The Journal of Social Psychology, volume 6, number 2, →DOI, →ISSN, page 252
Origin
Devised by Shinobu Ishihara, a professor at the University of Tokyo, who first published his tests in 1917.
Full word history & related roots →Cite this entry
Ishihara test. (n.d.). In WatkinsX Dictionary. Retrieved November 4, 2026, from https://dictionary.watkinsx.com/word/Ishihara%20test
“Ishihara test.” WatkinsX Dictionary, https://dictionary.watkinsx.com/word/Ishihara%20test. Accessed November 4, 2026.
WatkinsX Dictionary, s.v. “Ishihara test,” accessed November 4, 2026, https://dictionary.watkinsx.com/word/Ishihara%20test.
Source: Ishihara test on Wiktionary, CC BY-SA 4.0.