lum vs volcano

lum

noun
  • A ventilating chimney over the shaft of a mine. 

  • A chimney; also, the top part of a chimney. 

  • A deep pool, especially one in a riverbed. 

  • A grove or wood; also, a woody valley. 

volcano

noun
  • A kind of firework producing an upward plume of sparks. 

  • A vent or fissure on the surface of a planet (usually in a mountainous form) with a magma chamber attached to the mantle of a planet or moon, periodically erupting forth lava and volcanic gases onto the surface. 

verb
  • to erupt; to burst forth 

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