annular cataract n.
A congenital cataract in which a central white membrane replaces the nucleus.
- Annular eclipse
an eclipse of the sun in which a portion of its surface is visible as a ring surrounding the dark moon. Historical Examples Johnston suggests that the reference is to an annular eclipse which he finds occurred on August 14, at about 8¼ h. in the morning. The Story of Eclipses George Chambers Baron de […]
- Annular gear
. a gear having teeth cut on an inner cylindrical surface.
- Annular ligament
the ligamentous envelope surrounding a part, as the joints of the wrist or ankle or the head of the radius. Historical Examples Paleys account of the function of the annular ligament at the ankle is correct, and strikingly put. Parallel Paths Thomas William Rolleston It lies along the Radius, and passeth under the annular ligament. […]
- Annular ring
annular ring annular ring n. An opaque area appearing in radiographs of the lung and indicating a cavity of tuberculosis. Also called pleural ring. Historical Examples To hold the piston rings or ring in place, a junk ring is employed, being an annular ring bolted to the piston. Modern Machine-Shop Practice, Volumes I and II […]