be of unsound mind

To have impaired or dysfunctional thought, memory, and/or cognitive understanding; unable to think and/or understand for oneself. My poor grandfather has been of unsound mind ever since he suffered that stroke last year.

Common Names:

Name	Pronounced	Usage
Wickaninnish	wik-ə-NIN-ish (English)	Native American, Nuu-chah-nulth
Armel	-	French
Beatrycze	be-ah-TRI-che	Polish
Auberon	O-bər-ahn	English (Rare)
Tsisana	-	Georgian
Minodora	-	Romanian