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

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

“We know the central premise behind mental health diversion is that if we obtain mental health treatment for those that are mentally ill that are committing crimes, the public will be safer,” he said.

From Los Angeles Times • Jan. 8, 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

But some of his constituents view him as too developer-friendly for his housing policies and have criticized his past policies around expanding conservatorships for mentally ill people.

From Los Angeles Times • Oct. 18, 2025

You didn’t have to work the galleries long to realize that a large proportion of inmates were mentally ill.

From "Newjack: Guarding Sing Sing" by Ted Conover