The Collaborative International Dictionary
Semicircular \Sem`i*cir"cu*lar\, a.
Having the form of half of a circle.
--Addison.
Semicircular canals (Anat.), certain canals of the inner ear. See under Ear.
Wikipedia
The semicircular canals or semicircular ducts are three semicircular, interconnected tubes located in the innermost part of each ear, the inner ear. The three canals are the horizontal, superior and posterior semicircular canals.
Usage examples of "semicircular canals".
The decision was helped by the fact that I still didn't feel quite myself, even aside from the difference of opinion between my eyes and my semicircular canals as to which way was up and which was down.
Their stomachs and the semicircular canals of their ears had been through the ordeal before.
The ability to balance depends upon sensations derived through the eyes, from touching, but mainly from the semicircular canals of the internal ears.