Stupid, a.
Etymology: [L. stupidus, fr. stupere to be stupefied: cf. F. stupide.]
1. Very dull; insensible; senseless; wanting in understanding; heavy; sluggish; in a state of stupor; -- said of persons. O that men . . . should be so stupid grown . . . As to forsake the living God! Milton. With wild surprise, A moment stupid, motionless he stood. Thomson.
2. Resulting from, or evincing, stupidity; formed without skill or genius; dull; heavy; -- said of things. Observe what loads of stupid rhymes Oppress us in corrupted times. Swift.
Syn. -- Simple; insensible; sluggish; senseless; doltish; sottish; dull; heavy; clodpated. -- Stu"pid*ly, adv. -- Stu"pid*ness, n.
Shades of meaning
Fernald has no entry of its own for stupid; he lists it under absurd, brutish.
He lists it without comment; the entries above explain its neighbors.