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glaucoma

(Encyclopedia)glaucoma glôkōˈmə [key], ocular disorder characterized by pressure within the eyeball caused by an excessive amount of aqueous humor (the fluid substance filling the eyeball). This causes pressure...

Lyme disease

(Encyclopedia)Lyme disease or Lyme borreliosis, a nonfatal bacterial infection that causes symptoms ranging from fever and headache to a painful swelling of the joints. The first American case of Lyme's characteris...

toxoplasmosis

(Encyclopedia)toxoplasmosis, infection caused by Toxoplasma gondii, a single-celled parasitic microorganism that can infect most warm-blooded animals but reproduces only in animals of the cat family, who shed the p...

Hammurabi

(Encyclopedia)Hammurabi hämo͝oräˈbē [key], fl. 1792–1750 b.c., king of Babylonia. He founded an empire that was eventually destroyed by raids from Asia Minor. Hammurabi may have begun building the tower of B...

Pleiades, in astronomy

(Encyclopedia)Pleiades plēˈədēz, plīˈ– [key], in astronomy, famous open star cluster in the constellation Taurus; cataloged as M45. The cluster consists of some 500 stars, has a diameter of 35 light-years, ...

sewing machine

(Encyclopedia)sewing machine, device that stitches cloth and other materials. An attempt at mechanical sewing was made in England (1790) with a machine having a forked, automatic needle that made a single-thread ch...

macular degeneration

(Encyclopedia)macular degeneration, eye disorder causing loss of central vision. The affected area, the macula, lies at the back of the retina and is the part that produces the sharpest vision. The most serious vis...

Robinson, Theodore

(Encyclopedia)Robinson, Theodore, 1852–96, American painter, b. Irasburg, Vt. Beginning his career as a realist, Robinson was profoundly influenced by his meeting with Monet in 1888. Translating the impressionist...

Dayan, Moshe

(Encyclopedia)Dayan, Moshe mōˈshə dīänˈ, däyänˈ [key], 1915–81, Israeli military leader, b. Palestine. After attending Senior Agricultural School in Nahalal, Dayan fought with the Haganah (Jewish militia...

astigmatism

(Encyclopedia)astigmatism əstĭgˈmətĭzˌəm [key], type of faulty vision caused by a nonuniform curvature in the refractive surfaces—usually the cornea, less frequently the lens—of the eye. As a result, lig...