falsetto vs shrill

falsetto

noun
  • A person who sings in falsetto. 

  • The "false" (singing) voice in any human, usually airy and lacking a purity of vowels; created by utilizing the next highest vocal folds above those used for speech and normal range singing. It is commonly confused with the head voice register. 

verb
  • To sing or utter in falsetto. 

shrill

noun
  • A shrill sound. 

adj
  • Sharp or keen to the senses. 

  • Having a shrill voice. 

  • Fierce, loud, strident. 

  • High-pitched and piercing. 

verb
  • To make a shrill noise. 

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