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protanopia

noun

prot·​an·​opia ˌprōt-ə-ˈnō-pē-ə How to pronounce protanopia (audio)
: a dichromatism in which the spectrum is seen in tones of yellow and blue with confusion of red and green and reduced sensitivity to monochromatic lights from the red end of the spectrum

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“Protanopia.” Merriam-Webster.com Medical Dictionary, Merriam-Webster, https://www.merriam-webster.com/medical/protanopia. Accessed 4 Dec. 2025.

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