Usignolo translates to "nightingale". It's a beautiful and somewhat uncommon word in everyday Italian, making it stand out in the lyrics.
In the song, the nightingale is personified, saying, "Non era come immaginavo" (It wasn't as I imagined). This adds a poetic and melancholic touch, suggesting a disillusionment even after achieving something great, much like the artist's own reflections on success.
"Di Notte" ("At Night") is a nocturnal, atmospheric collaboration between Ernia, Sfera Ebbasta, and Carl Brave about moving through the city after dark. The verses follow someone walking alone through streets that feel faintly dangerous, then driving around with someone they care about, in no rush to get anywhere. Small nighttime rituals, drinks, phone calls, aimless driving, become the backdrop for looser reflection. Underneath the streetwise Italian trap textures, the song keeps returning to one idea: success and connection rarely arrive together, and chasing one often costs you the other. It closes on a quietly melancholic image, a night that didn't turn out the way it was imagined.