Definition of sacculus in US English:



  • 1The 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.

    • ‘The mechanism seems to be that noise energy is transmitted from the stapes footplate into the vestibular part of the labyrinth, especially to the sacculus and the utriculus.’
    • ‘The maculae consist of rather shapeless compartments known as the sacculus and utriculus.’
    • ‘Because the sacculus is buried deep within the ear, Todd and his colleagues could not measure its reaction to sound directly.’
    • ‘A characterization of the ion channels which make a hair cell electrically resonant was obtained via studies of the bullfrog sacculus, a receptor for ground-borne vibration and low-frequency sound.’
    1. 1.1
      another term for saccule
      • ‘Sacculus formation is common, but rupture of a sacculus is very rare.’
      • ‘This was accomplished by the evolution of a sacculus surrounding the cell.’
      • ‘Next to these developing scars, enlarged alveolar sacculi with loss of septae and bronchiolization were observed.’
      • ‘Ultrasonography is used for the diagnosis and follow-up of the progression of the uterine sacculus until its disappearance.’


Mid 18th century: from Latin, diminutive of saccus ‘sack’.