a uña de caballo

Spanish edit

(idiomatic) riding (a horse) as fast as one can
- 1891, Benito Pérez Galdós, Ángel Guerra:
  […] salir pitando para Portugal a uña de caballo.
  get out there and make for Portugal as fast as his horse's legs could carry him.
(idiomatic) like a bat out of hell
Synonyms: a matacaballo, con viento fresco, cagando hostias, cagando cerillas, cagando leches
- 1894, Ricardo Palma, Tradiciones peruanas, Monja y cartujo:
  Entretanto don Alonso escapó a uña de caballo, y doña Elvira se fue a Chuquisaca y se refugió en la casa materna.
  (please add an English translation of this quotation)