Reincarnaste comes from the verb reencarnar, meaning "to reincarnate". It's a striking and somewhat unexpected word to find in a pop song, making it memorable and intriguing.
In the context of the song, Belinda uses it metaphorically to express how her former lover has transformed or reappeared in a different, perhaps unrecognizable, version of themselves within her own being, or as a new person in her life. This dramatic imagery adds a unique depth to the lyrics about heartbreak and change.
Belinda opens "Alguien Más" with a dream that leaves her wrecked — "Tuve un sueño ayer, que me dejo con el alma rota" ["I had a dream yesterday, that left me with a broken heart"]. From there she traces a relationship that's already gone quiet on the other side: her heart trembles at no longer being held, and she admits she's become "el fantasma de tu voz" ["the ghost of your voice"] — still around, no longer heard.
The chorus keeps landing on the same admission, "Se muy bien que hay alguien más" ["I know very well that there's someone else"], said less like an accusation and more like something she's finally letting herself say out loud. She learned to love because of him, and still accepts that his kisses don't taste the same anymore. It's a breakup song built around naming the ending rather than fighting it.