hamada vs reg

hamada

noun
  • A high, desert landscape from which most of the sand has been removed by wind erosion 

reg

noun
  • A hard surface of rock fragments set in a sandy matrix, found in some hot deserts; regolith, stony desert. 

  • A regulation. 

  • registration 

  • registry 

  • registrar 

  • A regular. 

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