mayday vs squeal

mayday

noun
  • An international distress signal used by shipping and aircraft. 

squeal

noun
  • A high-pitched sound, such as the scream of a child or a female person, or noisy worn-down brake pads. 

  • The cry of a pig. 

verb
  • To make a squealing noise. 

  • To scream with a shrill, prolonged sound. 

  • To give sensitive information about someone to a third party; to rat on someone. 

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