Aurores literally translates to "dawns" or "daybreaks". It's a beautiful and somewhat poetic word that evokes new beginnings and the passage of time.
In the context of the song, Dalida uses "aurores" to question how many more dawns will pass while her love, which is tearing them apart, will see their bodies sing. It adds a layer of timelessness and a sense of enduring struggle to her emotional plea, making it a memorable and evocative choice.
Dalida spends this whole song asking a question she already suspects has no good answer: 'Dieu seul pourrait me dire, quand tout semble fini, pourquoi il veut détruire les cœurs qu'ils a unis' [God alone could tell me, when everything seems over, why he wants to destroy the hearts he united]. It's less an accusation than a genuine puzzle: something broke a love that was supposed to be settled, and she can't work out why.
She's not naive about it either. 'Pourtant dans la grande île, il y en avait tant à aimer' [Yet on this big island, there were so many to love], as if to say the loss wasn't down to a shortage of options. 'Mais Dieu sait-t-il lui même' [But does God himself know] leaves her wondering if even he's stuck on this one, and 'Pourquoi c'est toi que j'aime, et que j'aimerai jusqu'à la fin' [Why is it you that I love, and that I will love until the end] answers the question anyway, without waiting for God to. She never gets the explanation. She just keeps loving through it.