Obstinate and stupid; SYN. bullet-headed, pigheaded. bull-headed

Having sound judgment; sagacious; shrewd.

1. Not easily restrained; ungovernable; obstinate; stubborn.
2. Directed by ungovernable will, or proceeding from obstinacy.

Like a mule; sullen; stubborn.
Unreasonably and inflexibly obstinate

ETYM Latin obduratus, p. p. of obdurare to harden; ob + durare to harden, durus hard. Related to Dure.
1. Hardened in feelings, esp. against moral or mollifying influences; unyielding; hard-hearted; stubbornly wicked.
2. Hard; harsh; rugged; rough; intractable.
3. Obstinate; hard-hearted.

ETYM Latin obstinatus, p. p. of obstinare to set about a thing with firmness, to persist in; ob (see Ob-) + a word from the root of stare to stand. Related to Stand, Destine.
Persisting in a reactionary stand; SYN. stubborn, unregenerate.

ETYM Old Eng. stoburn, stiborn; probably from as. styb a stub. Related to Stub.
1. Difficult to treat or deal with.
2. Tenaciously unwilling or marked by tenacious unwillingness to yield.