• WordNet 3.6
    • n pertinacity persistent determination
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Webster's Revised Unabridged Dictionary
    • n Pertinacity The quality or state of being pertinacious; obstinacy; perseverance; persistency.
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Century Dictionary and Cyclopedia
    • n pertinacity The character of being pertinacious; resoulute or unyieding adherence, as to an opinion, purpose, design, course of action, etc.; persistency; obstinacy; resoluteness: as, to cling with pertinacity to one's purpose.
    • n pertinacity Synonyms See pertinacious.
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Chambers's Twentieth Century Dictionary
    • Pertinacity quality of being pertinacious or unyielding: obstinacy: resoluteness
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Webster's Revised Unabridged Dictionary
Cf. F. pertinacité,
Chambers's Twentieth Century Dictionary
Fr.,—L. pertinax, -acis, holding fast—per, thoroughly, tenax, tenacious—tenēre, to hold.


In literature:

They all write about death with a pertinacity that is positively astounding.
"Modern Women and What is Said of Them" by Anonymous
He argued against universal suffrage with equal pertinacity.
"The English Utilitarians, Volume I." by Leslie Stephen
The pertinacity with which he adheres to his purposes yields only to the immediate pressure of fear.
"Critical and Historical Essays, Volume III (of 3)" by Thomas Babington Macaulay
His services were, however, required, and his pertinacity in retaining our friendship was not so unwelcome.
"A Yacht Voyage to Norway, Denmark, and Sweden" by W. A. Ross
The old man stuck heroically to his post, and the pig stuck with equal pertinacity to his course.
"Holiday Tales" by W. H. H. Murray
There was quite as much vigor and pertinacity in her movements as if she were just starting out for the day.
"Sword and Pen" by John Algernon Owens
The alternative was too dreadful for her to withstand my pertinacity.
"A Romantic Young Lady" by Robert Grant
We were stared at with almost incredible pertinacity and good humour.
"Rambles Beyond Railways;" by Wilkie Collins
He has the artistic temperament, but he has also the pertinacity of genius.
"The Light of the Star" by Hamlin Garland
Still, there was a kind of respectful pertinacity about him.
"Scally" by Ian Hay