gyral vs gyratory

gyral

adj
  • Moving circularly or spirally; gyratory; whirling. 

  • Of or pertaining to a gyrus 

gyratory

adj
  • Moving in a circle, or spirally; revolving; whirling around. 

noun
  • A large traffic roundabout with non-standard lane markings or priorities, or with buildings on the central island. 

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