sacculus

 
Pronunciation: /ˈsakjʊlʊs/

noun

Anatomy
  • the smaller of the two fluid-filled sacs forming part of the labyrinth of the inner ear (the other being the utriculus). It contains a region of hair cells and otoliths which send signals to the brain concerning the orientation of the head.
  • another term for saccule.

Origin:

mid 18th century: from Latin, diminutive of saccus 'sack'