pervicacious

per•vi•ca•cious (pur-vi-KEY-shuhs)  adj

Definition:
extremely willful; obstinate; stubborn

pervicaciousness noun; pervicaciously adverb

Origin:
1625–35;  from Latin pervica-c-,  s. of pervica-x  stubborn, willful ( per-  + vic-,  var. s. of vincere  to conquer  + -a-x  adj. suffix denoting tendency or ability) + -ious

Related:
Synonyms: adamant, bullheaded, cantankerous, contumacious, inexorable, inflexible, intractable, mulish, obdurate, pertinacious, pigheaded,  refractory, tenacious, unbending, unreasonable, unshakable, willful

Sentence Examples:
• For a girl to lay so much stress upon going to church, and yet resolve to defy her parents, in an article of the greatest consequence to them, and to the whole family, is an absurdity.  You are recommended, Miss, to the practice of your private devotions.  May they be efficacious upon the mind of one of the most pervicacious young creatures that ever was heard of! -Clarissa, Samuel Richardson

• Of late, I am told by shopkeepers, the tin box with the pervicacious cover is becoming popular; but I remain true to my sponge in a bottle: for, unlike the leopard, I am able to change my spots. -The Perfect Gentleman, Ralph Bergengren

• It happened a little while thereafter that he made a most heavy regret thereof to his father, attributing the causes of his bad success in pacificatory enterprises to the perversity, stubbornness, froward, cross, and backward inclinations of the people of his time; roundly, boldly, and irreverently upbraiding, that if but a score of years before the world had been so wayward, obstinate, pervicacious, implacable, and out of all square, frame, and order as it was then, his father had never attained to and acquired the honour and title of Strife-appeaser so irrefragably, inviolably, and irrevocably as he had done.  -Gargantua and Pantagruel, Francois Rabelais

The Storyline
... not the least of which was due to his pervicaciousness in fighting these petty battles.

Sources: Dictionary.com

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