beep vs murmur

beep

verb
  • To sound (something that makes a beep). 

  • To contact (someone via) a pager device. 

  • To telephone a person, only allowing the phone to ring once, in order to request a call back. 

  • To produce a beep. 

  • To have sexual intercourse with - referring to the bleep tone used to censor obscene words in broadcasts 

noun
  • A message sent to a pager device. 

  • A short, electronically produced tone. 

  • The sound produced by the horn of a car, or any similar sound. 

murmur

verb
  • To speak or make low, indistinguishable noise; to mumble, mutter. 

  • To say (something) indistinctly, to mutter. 

noun
  • The sound made by any condition which produces noisy, or turbulent, flow of blood through the heart. 

  • A muttered complaint or protest; the expression of dissatisfaction in a low muttering voice; any expression of complaint or discontent. 

  • Soft indistinct speech. 

  • Any low, indistinct sound, like that of running water. 

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