hill vs tussock

hill

noun
  • A heap of earth surrounding a plant. 

  • 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 sloping road. 

  • The pitcher’s mound. 

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

verb
  • To form into a heap or mound. 

  • To heap or draw earth around plants. 

tussock

noun
  • A tuft or clump of green grass or similar verdure, forming a small hillock. 

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