obstinate (adj.)
mid-14c., from Latin obstinatus “resolute, resolved, determined, inflexible, stubborn,” past participle of obstinare “persist, stand stubbornly, set one’s mind on,” from ob “by” (see ob-) + stinare (related to stare “stand”), from PIE *ste-no-, from root *sta- “to stand, make or be firm.”1
Definition of obstinate
1: stubbornly adhering to an opinion, purpose, or course in spite of reason, arguments, or persuasion
2: not easily subdued, remedied, or removed2
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1
https://www.etymonline.com/word/obstinate [last accessed 25 April 2018].
2
https://www.merriam-webster.com/dictionary/obstinate [last accessed 25 April 2018].