Nier vs. démentir

In the French language, 'nier' and 'démentir' are both verbs that relate to the act of denying but are used in slightly different contexts with different nuances. Understanding the distinction between the two can aid in accurate expression in both spoken and written discourse.

Nier

'Nier' is a verb that means 'to deny' in a broad sense. It is used to reject the truth of a statement or to refuse to admit the existence or reality of something.
Il nie avoir jamais vu cette personne.
(He denies ever having seen this person.)
Elle nie la présence de problèmes dans son équipe.
(She denies the presence of problems in her team.)

Démentir

'Démentir' is also a verb that means 'to deny', but it often implies providing some form of proof or refutation. It is used when contradicting a fact, rumor, or allegation more formally.
Le ministre a démenti les rumeurs de démission.
(The minister denied the resignation rumors.)
L'entreprise a démentir les accusations portées contre elle.
(The company had to deny the accusations made against it.)

Summary

While both 'nier' and 'démentir' translate to 'to deny', 'nier' is generally used in a broader sense for refusing to acknowledge something, whereas 'démentir' involves a more formal refutation or counteracting of an assertion, often backed by evidence.