cowlick vs hairstyle

cowlick

noun
  • An unruly lock or section of hair that sticks straight out from the skull or lies at an angle at odds with the rest of an individual's hair, like a whorl or vortex. 

hairstyle

noun
  • The style in which someone's hair has been cut and arranged. 

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