hothouse vs tumble dryer

hothouse

noun
  • A heated room for drying greenware. 

  • An environment in which growth or development is encouraged naturally or artificially; a hotbed. 

  • A heated greenhouse. 

  • A hot state in global climate. 

verb
  • To provide (a child) with an enriched environment with the aim of stimulating academic development. 

tumble dryer

noun
  • An electrical device that dries clothes in a rotating drum which tumbles the clothes in a flow of hot air. 

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