Puñal literally translates to "dagger" or "knife". It's a strong and evocative word that immediately brings to mind pain and betrayal.
In the context of the song, Farruko sings, "Siento un puñal en el alma" (I feel a dagger in my soul). He uses this powerful metaphor to express the deep, sharp pain and grief he feels over the loss of a loved one to street violence, making it a memorable and impactful word.
Farruko and Divino wrote this for a friend the street took. The chorus names the wound and then refuses to explain it — "Siento un puñal en el alma" ("I feel a dagger in my soul"), "Un dolor que nada lo calma" ("a pain that nothing calms") — while the verses stay in small, exact scenes: going to the wake and walking straight back out, "Fui al velorio pero no aguanté, me desaparecí" ("I went to the wake but I couldn't take it, I disappeared"); the warnings that never landed, "Te di pila de consejos pero no se te instaló" ("I gave you piles of advice but it never installed in you"); a Sunday he wants to keep, a kiss on the forehead.
What the song turns on is how little notice death gave. "La muerte no pide permiso ni toca ni te da advertencia" ("death asks no permission, doesn't knock, gives you no warning") — "Solo llega y ya" ("it just arrives, and that's that"), repeated until it stops sounding like a phrase and starts sounding like the thing itself. The last verse turns outward to whoever is still out there: "La calle no es juego, brother" ("the street is no game, brother"), "Esto no es GTA" ("this isn't GTA"), "Aquí no le puedes dar restart, yeah" ("here you can't hit restart"). Farruko dedicates it out loud to everyone the street has taken someone from, and to the soldiers who are not here with us.