backside vs tush

backside

noun
  • A person's buttocks. 

  • Used other than figuratively or idiomatically: see back, side. 

  • The back side of an estate: the backyard and outbuildings behind a main house, especially (UK dialect, euphemistic) an outhouse. 

  • The reverse or opposite of anything. 

adj
  • Used other than figuratively or idiomatically: see back, side. 

  • Approaching an obstacle backward 

tush

noun
  • The buttocks. 

  • A tusk. 

  • Nonsense; tosh. 

  • A small tusk sometimes found on the female Indian elephant. 

intj
  • An exclamation of contempt or rebuke. 

verb
  • To express contempt; rebuke. 

  • To pull or drag a heavy object such as a tree or log. 

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