hairdressing vs ponytail

hairdressing

noun
  • The washing, colouring, cutting and styling of the hair; the art or trade of a hairdresser. 

ponytail

noun
  • A hairstyle where the hair is pulled back and tied into a single "tail" which hangs down behind the head. 

verb
  • To form (the hair) into a ponytail. 

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