flashlight vs top light

flashlight

noun
  • A battery-powered hand-held light source. 

  • A flashgun (device used to create flashes of light for photography). 

verb
  • To illuminate with a flashlight. 

top light

noun
  • Light from above; toplighting. 

  • Any glazing above a main window, partition or door 

  • A skylight. 

  • The upper (and usually smaller) part (casement) of a window, often hinged a the top 

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