bray vs drone

bray

noun
  • Any discordant, grating, or harsh sound. 

  • The cry of an animal, now chiefly that of animals related to the ass or donkey, or the camel. 

verb
  • To make or utter (a shout, sound, etc.) discordantly, loudly, or in a harsh and grating manner. 

  • Of an animal (now chiefly of animals related to the ass or donkey, and the camel): to make its cry. 

  • To make a harsh, discordant sound like a donkey's bray. 

  • To hit (someone or something). 

drone

noun
  • A humming or deep murmuring sound. 

  • One of the fixed-pitch pipes on a bagpipe. 

  • One who performs menial or tedious work. 

  • A person without the ability to think critically and independently, especially one who follows a group blindly; a non-player character. 

  • A remotely controlled aircraft, an unmanned aerial vehicle (UAV). 

  • A Toyota HiAce or a similar van, especially one used by Ugandan state agents to kidnap opposition members. 

  • A male ant, bee or wasp, which does not work but can fertilize the queen. 

  • A genre of music that uses repeated lengthy droning sounds. 

  • A low-pitched hum or buzz. 

verb
  • To speak in a monotone way. 

  • To produce a low-pitched hum or buzz. 

  • To kill with a missile fired by unmanned aircraft. 

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