Déraille comes from the verb dérailler, meaning "to derail" or "to go off the rails." It's a vivid and somewhat dramatic word that isn't used in everyday conversation.
In the song, it's used metaphorically in the line "Pour guérir avant que tout déraille" (To heal before everything derails). It perfectly captures the idea of life spiraling out of control or falling apart, adding a sense of urgency and impending chaos to the narrative.
Have you ever felt like you and someone else were just meant to be, like you had a 'royal life' together? That's exactly what Izïa explores in "Royale." It's a beautiful, bittersweet look at a deep connection, maybe with a parent or a very close friend, where they grew up 'main dans la main' [hand in hand].
Izïa sings about how this person helped her, even saying 'C'est toi qui apaisais ma colère' [It was you who soothed my anger]. But even in this 'royal life,' there are regrets, like 'À toutes ces fois où j'm'en suis voulu / Et toutes les autres fois où je n't'ai pas entendu' [To all those times I blamed myself / And all the other times I didn't listen to you]. It's a powerful reminder that even the strongest bonds have their challenges, and sometimes, life just takes us by surprise, but we learn and we get back up.