ooid vs orbed

ooid

adj
  • Shaped like an egg; ovoid; ovate. 

noun
  • A small calcium carbonate or iron coated grain found on the seafloor. 

orbed

adj
  • Having the form of an orb; round; spherical. 

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