idiotic

Idiotic, Idiotical, a.

Etymology: [L. idioticus ignorant, Gr. idiotique. See Idiot.]

1. Common; simple. [Obs.] Blackwall.

2. Pertaining to, or like, an idiot; characterized by idiocy; foolish; fatuous; as, an idiotic person, speech, laugh, or action.

Shades of meaning

Fernald lists idiotic only as an antonym, under astute, clever.

He lists it without comment; the entries above explain its neighbors.

none given