mentally ill

American  

adjective

1. having a mental illness.

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noun

(used with a plural verb)

1. Usually the mentally ill mentally ill persons collectively.

Etymology

Origin of mentally ill

First recorded in 1935–40

Example Sentences

He had been placed in Atascadero State Hospital, a maximum-security prison for mentally ill convicts located between Los Angeles and San Francisco.

From Los Angeles Times • Mar. 2, 2026

Wiseman caused instant controversy with his first film, "Titicut Follies," which remains one of his most famous documentaries, shot in 1967 and capturing the bleak reality of an asylum for the mentally ill, Bridgewater.

From Barron's • Feb. 16, 2026

“The Housemaid” would be enjoyable enough had Seyfried only been giving a layered performance as a mentally ill housewife.

From Salon • Jan. 31, 2026

In 1811, Saxony’s king converted it into a model asylum for the mentally ill, and for many years it was.

From The Wall Street Journal • Nov. 24, 2025

My mother, working with mentally ill people every day, noticed I was acting funny and started asking me questions.

From "When I Was the Greatest" by Jason Reynolds