Entêtement vs. obstination vs. opiniâtreté
While "entêtement", "obstination", and "opiniâtreté" are all synonyms for stubbornness, they differ in nuance and register. "Entêtement" is typically negative and implies irrationality. "Obstination" is stronger and focuses on the refusal to yield, which can be seen as either annoying or determined. "Opiniâtreté" is a more formal, often positive term referring to admirable tenacity and endurance over time.
Entêtement
B2This word usually carries a negative connotation, suggesting a refusal to listen to reason or logic. It describes someone who acts pig-headed, behaves childishly, or sticks to an idea simply because they do not want to admit they are wrong.
Son entêtement à ne pas demander son chemin nous a fait perdre une heure.
(His stubbornness in not asking for directions made us lose an hour.)
C'est de l'entêtement pur, car il sait très bien que j'ai raison.
(It is pure pig-headedness, because he knows very well that I am right.)
L'entêtement de l'enfant à ne pas manger ses légumes a fatigué ses parents.
(The child's stubborn refusal to eat his vegetables exhausted his parents.)
Obstination
C1This term refers to a firm will to continue in a path or idea despite difficulties or opposition. It is stronger than "entêtement" and implies a blockade; it can be negative (useless persistence) or neutral/positive (refusing to back down in a negotiation).
Grâce à son obstination, la police a fini par retrouver le coupable.
(Thanks to her persistence, the police finally found the culprit.)
L'obstination du vendeur à sonner à ma porte devient harcelante.
(The salesperson's persistence in ringing my doorbell is becoming harassing.)
Il continue ses recherches avec une obstination froide et calculée.
(He continues his research with a cold and calculated stubbornness.)
Opiniâtreté
C2This is a literary and often positive word describing energetic perseverance and tenacity. It implies a long-term struggle where one displays willpower and courage to achieve a difficult goal.
Elle a appris le violon avec une opiniâtreté admirable malgré son âge.
(She learned the violin with admirable tenacity despite her age.)
Les pompiers ont combattu le feu avec une rare opiniâtreté toute la nuit.
(The firefighters fought the fire with rare tenacity all night long.)
Sa réussite est le fruit de son talent et de son opiniâtreté au travail.
(His success is the fruit of his talent and his tenacity at work.)
Summary
To summarize: use "entêtement" for irrational or childish refusal (blind stubbornness); use "obstination" for a firm resolve to continue despite resistance (persistence); and use "opiniâtreté" for noble, long-term perseverance (tenacity).