hydroa

noun

hy·​droa hī-ˈdrō-ə How to pronounce hydroa (audio)
: an itching usually vesicular eruption of the skin
especially : one induced by exposure to light

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“Hydroa.” Merriam-Webster.com Medical Dictionary, Merriam-Webster, https://www.merriam-webster.com/medical/hydroa. Accessed 30 Oct. 2025.

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