thigh boot vs wader

thigh boot

noun
  • A boot that rises as high as the wearer's thigh. 

wader

noun
  • A waterproof boot that comes up to the hip, used by fishermen, etc. 

  • One who wades. 

  • A long-legged bird associated with wetland or coastal environments. 

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