An expression used primarily in Latin America, 'meterle fierro' translates to 'put the pedal to the metal' or 'go full throttle'. It is used metaphorically to indicate that someone is making a big effort or working hard on something.
Examples
- Spanish: Vamos a tener que meterle fierro a este proyecto si queremos terminarlo a tiempo.
- English: We're going to have to put the pedal to the metal on this project if we want to finish it on time.