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. "You do not well in obstinacy To cavil in the course of this contract." "To shelter their ignorance, or obstinacy, under the obscurity of their terms."