dripstone vs garret

dripstone

noun
  • A protective moulding over a door or window that allows rain to drip away from the structure. 

  • Stalactites and stalagmites collectively. 

  • A water filter in which impurities are removed by running water through a porous stone. 

garret

noun
  • An attic or semi-finished room just beneath the roof of a house. 

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