insomniac

noun
in·​som·​ni·​ac | \ -nē-ˌak How to pronounce insomniac (audio) \

Medical Definition of insomniac

 (Entry 1 of 2)

: one affected with insomnia

insomniac

adjective

Medical Definition of insomniac (Entry 2 of 2)

: affected with insomnia an insomniac patient

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Britannica English: Translation of insomniac for Arabic Speakers

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