buzz vs knock out

buzz

verb
  • To communicate with (a person) by means of a buzzer. 

  • To fly while making such a sound. 

  • To show a high level of activity and haste, energization or excitement, to be busy as a bee in one’s actions but perhaps mentally charged. 

  • Of a group of people, to talk about some interesting topic excitedly. 

  • To whisper; to communicate, as tales, in an undertone; to spread, as a report, by whispers or secretly. 

  • To make a low, continuous, humming or sibilant sound, like that made by bees with their wings. 

  • To fly at high speed and at a very low altitude over a specified area, as to make a surprise pass. 

  • To talk to incessantly or confidentially in a low humming voice. 

  • To utter a murmuring sound; to speak with a low, humming voice. 

  • To cut the hair in a close-cropped military style, or buzzcut. 

noun
  • Major topic of conversation; widespread rumor; information spread behind the scenes. 

  • Synonym of fizz-buzz (“counting game”) 

  • The audible friction of voiced consonants. 

  • A whisper. 

  • A rush or feeling of energy or excitement; a feeling of slight intoxication. 

  • A continuous humming noise, as of bees; a confused murmur, as of general conversation in low tones. 

  • A telephone call or e-mail. 

knock out

verb
  • To communicate (a message) by knocking. 

  • To fall asleep, especially suddenly. 

  • To lose the scent of hounds in fox-hunting. 

  • To eliminate from a contest or similar. 

  • To put to sleep. 

  • To complete, especially in haste; knock off. 

  • To render unconscious, as by a blow to the head. 

  • To strike or bump (someone or something) out. 

  • To exhaust. 

  • To cause a mechanism to become non-functional by damaging or destroying it. 

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