DIGESTER n. 3 definitions
A strong closed vessel, in which bones or other substances may be subjected, usually in water or other liquid, to a temperature above that of boiling, in order to soften them.
DIOPTRICS n.
n of light in passing from one medium into another, or through different mediums, as air, water, or glass, and esp. through different lenses; -- distinguished from catoptrics, which refers to reflected light.