Definition of pertinacious
1a : adhering resolutely to an opinion, purpose, or designb : perversely persistent
2 : stubbornly tenacious
pertinacityplay \ˌpər-tə-ˈna-sə-tē\ noun
pertinacious was our Word of the Day on 11/18/2012. Hear the podcast!
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
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.
Origin and Etymology of pertinacious
Latin pertinac-, pertinax, from per- thoroughly + tenac-, tenax tenacious, from tenēre
First Known Use: 1583
Synonym Discussion of pertinacious
Seen and Heard
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