greenhouse vs sow

greenhouse

verb
  • To place (plants) in a greenhouse. 

  • To nurture in order to promote growth. 

noun
  • A building used to grow plants, particularly one with large glass windows or plastic sheeting to trap heat from sunlight even in intemperate seasons or climates. 

  • A hot state in global climate. 

  • A structure that shields the operating table to protect against bacteria. 

sow

verb
  • To scatter, disperse, or plant (seeds). 

  • To scatter over; to besprinkle. 

  • To spread abroad; to propagate. 

noun
  • A mass of metal solidified in a mold. 

  • A sowbug. 

  • A female bear, she-bear. 

  • A contemptible, often fat woman. 

  • A female guinea pig. 

  • A channel that conducts molten metal to molds. 

  • A kind of covered shed, formerly used by besiegers in filling up and passing the ditch of a besieged place, sapping and mining the wall, etc. 

  • A female pig. 

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