bank up vs hill

bank up

verb
  • To press a mound of something against something else. 

  • To make a mound to guard against something. 

hill

verb
  • To form into a heap or mound. 

  • To heap or draw earth around plants. 

noun
  • A single cluster or group of plants growing close together, and having the earth heaped up about them. 

  • An elevated landmass smaller than a mountain. 

  • A heap of earth surrounding a plant. 

  • A sloping road. 

  • The pitcher’s mound. 

  • The raised portion of the surface of a vinyl record. 

How often have the words bank up and hill occurred in a corpus of books? (source: Google Ngram Viewer )