hothouse vs incubator

hothouse

noun
  • A heated greenhouse. 

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

  • A heated room for drying greenware. 

  • A hot state in global climate. 

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

incubator

noun
  • A place to maintain the culturing of bacteria at a steady temperature. 

  • An apparatus used to maintain environmental conditions suitable for a newborn baby. 

  • Any apparatus used to maintain environmental conditions suitable for a reaction. 

  • A support programme for the development of entrepreneurial companies. 

  • An apparatus used to maintain environmental conditions suitable for the hatching of eggs. 

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