semicircular canal ampulla
The spherical enlargement at the base of each semicircular canal where they connect with the utricle, containing the crista ampullaris which detects movement of the fluid within the canals [ http://en.wikipedia.org/wiki/Osseous_ampullae ]
Term info
semicircular canal ampulla
pheno_slim
http://upload.wikimedia.org/wikipedia/commons/6/65/Vestibular_system%27s_semicircular_canal-_a_cross-section.jpg
TODO check duct vs canal. Also check FMA - has many subtypes of semicircular canal such as 'ampulla of anterior semicircular canal'
uberon
semicircular duct ampulla, membraneous ampulla of the semicircular duct, ampullae osseae
UBERON:0004043