This is the 9210th most frequent French word.
convaincante
Convaincante: Convincing.
Here, 'convaincante' is used as an adjective to describe the quality of the argument presented, denoting its effectiveness in persuasion.
Elle a présenté une argumentation très convaincante.
She presented a very convincing argument.
In this case, 'convaincant(e)' (masculine/feminine form) serves as an adjective describing the quality of the speech that had a persuasive effect.
Son discours était si convaincant qu'il a changé d'avis.
Her speech was so convincing that he changed his mind.
Here, 'convaincantes' is an adjective modifying 'preuves' (evidence), emphasizing the degree to which the evidence was compelling and persuasive.