Imbecile

Part of speech: noun (n.)

One destitute of strength; esp., one of feeble mind.

Part of speech: verb (v.)

To weaken; to make imbecile; as, to imbecile men's courage. [Obs.] Jer. Taylor.

Part of speech: adjective (a.)

Destitute of strength, whether of body or mind; feeble; impotent; esp., mentally wea; feeble-minded; as, hospitals for the imbecile and insane.

Synonyms: Weak; feeble; feeble-minded; idiotic.