spa vs water closet

spa

noun
  • A hot tub. 

  • A trendy or fashionable resort. 

  • A convenience store. 

  • A health resort near a mineral spring or hot spring. 

  • A health club. 

  • A clumsy person (see spastic) 

  • An idiot; a gobshite 

water closet

noun
  • A flush toilet itself. 

  • Used other than figuratively or idiomatically: see water, closet. 

  • A room containing a flush toilet. 

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