corral vs let off

corral

verb
  • To capture or round up. 

  • To make a circle of vehicles, as of wagons so as to form a corral. 

  • To place inside of a corral. 

noun
  • An enclosure for livestock, especially a circular one. 

  • A circle of wagons, either for the purpose of trapping livestock, or for defense. 

  • An enclosure or area to concentrate a dispersed group. 

let off

verb
  • To cause to explode or come out; to release. 

  • To forgive and not punish. 

How often have the words corral and let off occurred in a corpus of books? (source: Google Ngram Viewer )