growl vs whistler

growl

noun
  • A low-pitched rumbling sound produced with a wind instrument. 

  • A similar sound made by a human. 

  • The rumbling sound made by a human's hungry stomach. 

  • An aggressive grumbling. 

  • A deep, rumbling, threatening sound made in the throat by an animal. 

verb
  • To play a wind instrument in a way that produces a low-pitched rumbling sound. 

  • To utter a deep guttural sound, as an angry animal; to give forth an angry, grumbling sound. 

  • Of a wind instrument: to produce a low-pitched rumbling sound. 

  • To send a user a message via the Growl software library. 

  • To express (something) by growling. 

whistler

noun
  • An audio-frequency electromagnetic wave produced by atmospheric disturbances such as lightning. 

  • The mountain beaver (Aplodontia rufa). 

  • The goldeneye (certain ducks of genus Bucephala). 

  • The whistling marmot (Marmota caligata). 

  • Someone or something that whistles, or who plays a whistle as a musical instrument. 

  • A broken-winded horse. 

  • Any of several passerine birds of the genera Pachycephala and Coracornis, of Australasia and the western Pacific. 

  • Any bird that whistles or is noted for its whistling vocalisations (applied regionally to various specific species). 

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