afferent vs optic

afferent

noun
  • An afferent structure or connection 

adj
  • Carrying towards. 

optic

noun
  • A lens or other part of an optical instrument that interacts with light. 

  • A measuring device with a small window, attached to an upside-down bottle, used to dispense alcoholic drinks in a bar. 

adj
  • Of, or relating to the eye or to vision. 

  • Of, or relating to optics or optical instruments. 

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