ob·sti·nate 
(ŏbstə-nĭt)
(ŏbstə-nĭt)adj.
1.
a. Stubbornly adhering to an attitude, opinion, or course of action; obdurate.
b. Characterized by such adherence: an obstinate refusal.
2. Difficult to manage, control, or treat: an obstinate problem; an obstinate headache.
[Middle English obstinat, from Latin obstinātus, past participle of obstināre, to persist; see stā- in the Appendix of Indo-European roots.]
obsti·nate·ly adv.
obsti·nate·ness n.
Synonyms: obstinate, stubborn, headstrong, recalcitrant, intractable, bullheaded, pigheaded, mulish
These adjectives mean tenaciously unwilling to yield. Obstinate implies unreasonable rigidity: "Mr. Quincy labored hard with the governor to obtain his assent, but he was obstinate" (Benjamin Franklin).
Stubborn pertains to innate, often perverse resoluteness or unyieldingness: "She was very stubborn when her mind was made up" (Samuel Butler).
One who is headstrong is obstinately bent on having his or her own way: The headstrong senator ignored his constituency. A person who is recalcitrant rebels against authority: The police arrested the recalcitrant protestors. Intractable refers to what is obstinate and difficult to manage or control: "the intractable ferocity of his captive" (Edgar Allan Poe).
Bullheaded suggests foolish or irrational obstinacy, and pigheaded, stupid obstinacy: Don't be bullheaded; see a doctor. "It's a pity pious folks are so apt to be pigheaded" (Harriet Beecher Stowe).
Mulish implies the obstinacy and intractability associated with a mule: "It is a mark of my own chalky insecurity and mulish youth that I hounded Andy every chance I got" (Brian Doyle).
These adjectives mean tenaciously unwilling to yield. Obstinate implies unreasonable rigidity: "Mr. Quincy labored hard with the governor to obtain his assent, but he was obstinate" (Benjamin Franklin).
Stubborn pertains to innate, often perverse resoluteness or unyieldingness: "She was very stubborn when her mind was made up" (Samuel Butler).
One who is headstrong is obstinately bent on having his or her own way: The headstrong senator ignored his constituency. A person who is recalcitrant rebels against authority: The police arrested the recalcitrant protestors. Intractable refers to what is obstinate and difficult to manage or control: "the intractable ferocity of his captive" (Edgar Allan Poe).
Bullheaded suggests foolish or irrational obstinacy, and pigheaded, stupid obstinacy: Don't be bullheaded; see a doctor. "It's a pity pious folks are so apt to be pigheaded" (Harriet Beecher Stowe).
Mulish implies the obstinacy and intractability associated with a mule: "It is a mark of my own chalky insecurity and mulish youth that I hounded Andy every chance I got" (Brian Doyle).