represents an object, generally an American muscle car like a Camaro or a Mustang, with great sex appeal. It's origin is in Latin America and the term is a Spanish/English mix. It translates as "panties down" implying girls willl eventually disrobe once in the car. It is known to be used in Panama, but does not seem common in Mexico. There are various web references and songs based on the term. Pussy magnet would be the equivalent term in American culture.
Car buyer: I want a hotrod, rough and fast, that the girls will dig.
Car salesman: You need to go with the a Camaro or Mustang, a musclecar that grabs attention and has the horspower to back it up. It's a baja panties.