Desarmar literally means "to disarm" or "to take apart". It's a powerful and versatile verb that's often used poetically in Spanish.
In the song, Reik sings "El corazón se me desarma", which translates to "My heart falls apart" or "My heart is disarmed". He uses this image to express a beautiful sense of vulnerability, as if love is dismantling all his defenses.
If you have ever felt like you were hitting rock bottom right before something miraculous happened, this track is for you. Mexican pop group Reik delivers an absolute power ballad about finding a love so strong that it completely resets your life. The singer admits he was on the verge of giving up after wandering through emotional mazes: "en un segundo de rendirme te encontré" ("one second before giving up, I found you"). Meeting this person changes everything instantly. When they are together, his defenses melt away—"el corazón se me desarma" ("my heart disarms itself")—and an exhausting personal tailspin finally stops: "detuvo mi caída libre" ("you stopped my free fall").
What makes the song click is how it treats painful memories as things that can actually be extinguished. The singer views his past as an "incendio que en tus brazos se apagó" ("a fire that was put out in your arms"). The phrase "mis fantasmas hoy por fin están en paz" translates literally to "my ghosts are finally at peace today," which is a dramatic, vivid way in Spanish to say that old regrets and haunting memories finally stopped bothering him. By trusting this new partner ("creo en ti" / "I believe in you"), the past gets pushed miles behind, turning a dangerous free fall into feeling completely indestructible.