Obstinacy

Webster's Dictionary of the English Language

·noun The quality or state of being difficult to remedy, relieve, or subdue; as, the obstinacy of a disease or evil.

II. Obstinacy ·noun A fixedness in will, opinion, or resolution that can not be shaken at all, or only with great difficulty; firm and usually unreasonable adherence to an opinion, purpose, or system; unyielding disposition; stubborness; pertinacity; persistency; contumacy.