per·​ti·​na·​cious | \ ˌpər-tə-ˈnā-shəs How to pronounce pertinacious (audio) \

Definition of pertinacious

1a : adhering resolutely to an opinion, purpose, or design
b : perversely persistent
2 : stubbornly tenacious

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Other Words from pertinacious

pertinaciously adverb
pertinaciousness noun
pertinacity \ ˌpər-​tə-​ˈna-​sə-​tē How to pronounce pertinacious (audio) \ noun

Choose the Right Synonym for pertinacious

obstinate, dogged, stubborn, pertinacious, mulish mean fixed and unyielding in course or purpose. obstinate implies usually an unreasonable persistence. an obstinate proponent of conspiracy theories dogged suggests an admirable often tenacious and unwavering persistence. pursued the story with dogged perseverance stubborn implies sturdiness in resisting change which may or may not be admirable. a person too stubborn to admit error pertinacious suggests an annoying or irksome persistence. a pertinacious salesclerk refusing to take no for an answer mulish implies a thoroughly unreasonable obstinacy. a mulish determination to have his own way

Did You Know?

If you say "pertinacious" out loud, it might sound familiar. That may be because if you take away the word's first syllable, you're left with something very similar to the word tenacious, which means "tending to adhere or cling." The similarity between "pertinacious" and "tenacious" isn't mere coincidence; both words derive from "tenax," the Latin word for "tenacious," and ultimately from the verb tenēre, meaning "to hold." Another descendant of "tenēre" is "tenure," a word that is typically used of the right to hold a job (especially a teaching position) for as long as desired.

Examples of pertinacious in a Sentence

a pertinacious little boy who was determined to catch and collect reptiles a pertinacious salesman who would simply not take “No!” for an answer
Recent Examples on the Web Barletta’s pertinacious reputation on immigration, from his time as mayor of Hazleton to his four terms in the U.S. House, is at center stage this year in his campaign to defeat Sen. Bob Casey’s bid for a third term. Chris Brennan,, "Lou Barletta rolls with Trump, as president shifts policy at border," 25 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'pertinacious.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of pertinacious

1583, in the meaning defined at sense 1a

History and Etymology for pertinacious

Latin pertinac-, pertinax, from per- thoroughly + tenac-, tenax tenacious, from tenēre

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The first known use of pertinacious was in 1583

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Cite this Entry

“Pertinacious.” Dictionary, Merriam-Webster, Accessed 15 May. 2021.

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