callback vs speak

callback

noun
  • A form of audience participation in which the audience shout lines in response to the dialog of a film. 

  • A joke which references an earlier joke in the same routine. 

  • A follow-up audition in casting. 

  • The return of a situation to a previous position or state. 

  • A function pointer passed as an argument to another function. 

  • A return telephone or radio call; especially one made automatically to authenticate a logon to a computer network. 

  • A product recall because of a defect or safety concern. 

speak

noun
  • Speech, conversation. 

  • language, jargon, or terminology used uniquely in a particular environment or group. 

verb
  • To communicate with one's voice, to say words out loud. 

  • To understand (as though it were a language). 

  • To have a conversation. 

  • To utter. 

  • To produce a sound; to sound. 

  • To be able to communicate in a language. 

  • Of a bird, to be able to vocally reproduce words or phrases from a human language. 

  • To deliver a message to a group; to deliver a speech. 

  • To be able to communicate in the manner of specialists in a field. 

  • To communicate or converse by some means other than orally, such as writing or facial expressions. 

  • To communicate (some fact or feeling); to bespeak, to indicate. 

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