pentice vs sprocket

pentice

noun
  • An extension of a building's roof and the protected area beneath. 

  • An unexcavated portion of a shaftway, intended to afford protection from falling debris to workers at the bottom of the shaft during certain stages of mining. 

  • A covered walkway. 

sprocket

noun
  • A flared extension at the base of a sloped roof. 

  • A toothed wheel that enmeshes with a chain or other perforated band. 

  • The tooth of such a wheel. 

  • A placeholder name for an unnamed, unspecified, or hypothetical manufactured good or product. 

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