Terrenal translates to "earthly" or "mundane." It's an interesting word choice because it contrasts with the divine or ethereal, often used to describe something grounded in the physical world.
In the song, Emmanuel describes "Ella" as "tan terrenal, pura y letal" (so earthly, pure, and lethal). This juxtaposition highlights her complex nature: she is real and tangible, yet also possesses a dangerous, almost supernatural allure. It's a captivating way to describe a woman who is both human and irresistibly powerful.
Emmanuel's "Ella" is all about a woman who completely captivates him. He describes her as everything and nothing, someone who knows him inside and out: "Ella en cada mirada, ella es todo y es nada / Siempre es ella, ella sabe todo de mí" [She in every glance, she is everything and nothing / It's always her, she knows everything about me]. She has a powerful hold over him, doing whatever she wants with him, and he seems to love it! She's more than just a fleeting moment; she's like a "suspiro en el viento" [a sigh in the wind].
He sees her as both earthly and divine, pure yet lethal, even calling her a "diosa con piel de mujer" [goddess with a woman's skin] who makes him fall. She's also a bit of a "criminal" and very jealous, causing him both good and bad feelings. He's totally consumed by her, wanting to love her until the end, even though she lives life with a "instinto suicida" [suicidal instinct] and loves as if she's about to die. For him, it's always and only her: "Sólo ella, siempre ella" [Only her, always her].