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neodymium

(Encyclopedia)neodymium nēˌōdĭmˈēəm [key], metallic chemical element; symbol Nd; at. no. 60; at. wt. 144.242; m.p. about 1,021℃; b.p. about 3,068℃; sp. gr. 7.004 at 20℃; valence +3. Neodymium is a lust...

marmot

(Encyclopedia)marmot, ground-living rodent of the genus Marmota, of the squirrel family, closely related to the ground squirrel, prairie dog, and chipmunk. Marmots are found in Eurasia and North America; the best-k...

woodpecker

(Encyclopedia)woodpecker, common name for members of the Picidae, a large family of climbing birds found in most parts of the world. Woodpeckers typically have sharp, chisellike bills for pecking holes in tree trun...

sun grebe

(Encyclopedia)sun grebe, common name for a tropical, mainly aquatic bird of the family Heliornithidae. Sun grebes, also called finfoots, are remarkable for their colorful, puffy-toed, webbed feet, which may serve a...

praseodymium

(Encyclopedia)praseodymium prāˌzēōdĭmˈēəm, –sēō– [key] [Gr., =green twin], metallic chemical element; symbol Pr; at. no. 59; at. wt. 140.90765; m.p. 931℃; b.p. 3,512℃; sp. gr. about 6.8; valence +...

rhea, in zoology

(Encyclopedia)rhea rēˈə [key], common name for a South American bird of the family Rheidae, which is related to the ostrich. Weighing from 44 to 55 lb (20–25 kg) and standing up to 60 in. (152 cm) tall, the rh...

chickenpox

(Encyclopedia)chickenpox or varicella vârˌəsĕlˈə [key], infectious disease usually occurring in childhood. It is caused by the same herpesvirus, varicella-zoster, that produces shingles; the virus can hide in...

necrotizing fasciitis

(Encyclopedia)necrotizing fasciitis, a quickly progressing infection of the skin that spreads along the fascia, the tissue that covers the muscles. (Necrotizing infections that spread along the outer skin layers ar...

acetaminophen

(Encyclopedia)acetaminophen əsētˌəmĭnˈəfĭn [key], an analgesic and fever-reducing medicine. It is an active ingredient in many over-the-counter medicines, including Tylenol and Midol. Introduced in the earl...

baldness

(Encyclopedia)baldness, thinning or loss of hair as a result of illness, functional disorder, or hereditary disposition; also known as alopecia. Male pattern baldness, a genetic trait, is the most common cause of b...