Crossword Dictionary

PERTINACIOUS

dogged, dour, persistent, pertinacious, tenacious, unyielding - a 
stubbornly unyielding; "dogged persistence"; "dour determination"; "the most vocal and pertinacious of all the critics"; "a mind not gifted to discover truth but tenacious to hold it"- T.S.Eliot; "men tenacious of opinion" 

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Synonyms

dogged, insistent, patient, persevering, persistent, tenacious

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Examples

Apart from his pertinacious fight for economy Hume was not always fortunate in his political activity.

The Cabetes, who possessed the soil, were fierce and pertinacious; and, assisted by the French, who traded to that coast, Coelho had to gain by inches what was granted him by leagues.

Extremely pertinacious in this respect, the poet went on attempting to storm the theatre, with assault upon assault, all practically failures until the seventh and last, which was unfortunately posthumous.

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Etymology

"unyielding, persistent, resolute" (in holding to a purpose, opinion, course of action, etc.), 1620s, from pertinacy "stubbornness" (late 14c.), from Latin pertinacia, from pertinax "very firm, tenacious" (see pertinacity) + -ous. Related: Pertinaciously.

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