Espinado is a poetic adjective that literally means "thorny" or "pricked by thorns," derived from the noun espina (thorn). It's a fantastic word that you won't hear in everyday conversation.
In this classic rock anthem, Santana uses it as a powerful metaphor. A 'corazón espinado' is a heart that has been hurt by love, feeling as if it's been pierced by thorns. This single word perfectly captures the song's central theme of agonizing heartache and unrequited love.
Ever been dumped so hard that living feels like a chore? That is the exact vibe Santana and Mexican rock band Maná channel here. The singer doesn't hold back his drama, kicking things off with “Esa mujer me está matando” ("That woman is killing me") because she left him with a “corazón espinado” ("thorned heart"). He complains that his soul refuses to listen to logic (“mi alma no da razón”) when he tries to forget her, leaving his poor chest feeling crushed and totally abandoned (“Mi corazón aplastado, dolido y abandonado”).
What makes this track fun is how intensely theatrical the misery gets. He cries out “Cómo duele, me duele mamá” ("How it hurts, it hurts me, mama"), calling for his mother like a wounded kid, before hitting a streak of pure spite. He warns his ex that karma is coming: “Pero no olvides mujer que algún día dirás: Cómo me duele el amor” ("Don't forget, woman, that one day you will say: How love hurts me"). It is a full-blown breakup lament powered by Carlos Santana’s fiery guitar, showing how agonizing it feels when you give everything to someone (“bien entregado”) and end up alone.