sac vs utricle

sac

noun
  • A bag or pouch inside a plant or animal that typically contains a fluid. 

  • A sacrifice. 

  • The privilege, formerly enjoyed by the lord of a manor, of holding courts, trying causes, and imposing fines; now used only in the phrase sac and soc or soc and sac. 

verb
  • To sacrifice. 

utricle

noun
  • The larger of the two fluid-filled cavities forming part of the membranous labyrinth in the vertebrate inner ear (the other being the saccule) and into which the semicircular canals open. It contains hair cells and otoliths which send signals to the brain concerning the orientation of the head. 

  • A dry indehiscent one-seeded fruit with thin membranous pericarp, similar to an achene and found in the beet and dock plants. 

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