encircling vs orbiculate

encircling

noun
  • encirclement 

adj
  • enclosing, skirting 

orbiculate

noun
  • That which is orbiculate, especially a solid whose vertical section is oval and whose horizontal section is circular. 

adj
  • spherical or circular; orbicular 

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