[ pur-tn-ey-shuhs ]
/ ˌpɜr tnˈeɪ ʃəs /
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See synonyms for: pertinacious / pertinaciously / pertinaciousness on Thesaurus.com


holding tenaciously to a purpose, course of action, or opinion; resolute.
stubborn or obstinate.
extremely or objectionably persistent: a pertinacious salesman from whom I could not escape.



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“Was” is used for the indicative past tense of “to be,” and “were” is only used for the subjunctive past tense.

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Origin of pertinacious

First recorded in 1620–30; pertinaci(ty) + -ous

OTHER WORDS FROM pertinacious

per·ti·na·cious·ly, adverbper·ti·na·cious·ness, noun
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2021

Example sentences from the Web for pertinacious

British Dictionary definitions for pertinacious

/ (ˌpɜːtɪˈneɪʃəs) /


doggedly resolute in purpose or belief; unyielding
stubbornly persistent

Derived forms of pertinacious

pertinaciously, adverbpertinacity (ˌpɜːtɪˈnæsɪtɪ) or pertinaciousness, noun

Word Origin for pertinacious

C17: from Latin pertināx, from per- (intensive) + tenāx clinging, from tenēre to hold
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012