catchment basin vs gully

catchment basin

noun
  • A topographic region in which all water drains to a common outlet. 

gully

noun
  • A trench, ravine or narrow channel which was worn by water flow, especially on a hillside. 

  • A road drain. 

  • A small valley. 

  • A fielding position on the off side about 30 degrees behind square, between the slips and point; a fielder in such a position 

  • A grooved iron rail or tram plate. 

  • A large knife. 

  • A drop kerb. 

  • an alleyway or side street. 

verb
  • To wear away into a gully or gullies. 

How often have the words catchment basin and gully occurred in a corpus of books? (source: Google Ngram Viewer )