inner ear vs pinna

inner ear

noun
  • The portion of the ear located within the temporal bone which includes the semicircular canals, vestibule, and cochlea and is responsible for hearing and balance. 

  • Mind's ear. 

pinna

noun
  • The visible part of the ear that resides outside of the head, the auricle; outer ear excluding the ear canal. 

  • A feather, wing, fin, or other similar appendage. 

  • A leaflet or primary segment of a pinnate compound leaf. 

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