unreasonably obstinate; obstinately unmoving

a stubborn child.

fixed or set in purpose or opinion; resolute

a stubborn opponent of foreign aid.

obstinately maintained, as a course of action

a stubborn resistance.

difficult to manage or suppress

a stubborn horse; a stubborn pain.

hard, tough, or stiff, as stone or wood; difficult to shape or work.

noun

die-hardism , grimness , implacability , implacableness , incompliance , incompliancy , inexorability , inexorableness , inflexibility , inflexibleness , intransigence , intransigency , obduracy , obdurateness , relentlessness , remorselessness , rigidity , rigidness