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menopause

(Encyclopedia)menopause klīmăkˈtərĭk, klīˌmăktĕrˈĭk [key], transitional phase in a woman's life when the ovaries stop releasing eggs, ovarian production of estrogen and other hormones tapers off, and men...

lever

(Encyclopedia) CE5 Classes of levers: A first-class lever (A), a second-class lever (B), and a third-class lever (C) lever, simple machine consisting of a bar supported at some stationary point along its length ...

liquid

(Encyclopedia)liquid, one of the three commonly recognized states in which matter occurs, i.e., that state, as distinguished from solid and gas, in which a substance has a definite volume but no definite shape. T...

dam

(Encyclopedia)dam, barrier, commonly across a watercourse, to hold back water, often forming a reservoir or lake; dams are also sometimes used to control or contain rockslides, mudflows, and the like in regions whe...

clam

(Encyclopedia)clam, common name for certain bivalve mollusks, especially for marine species that live buried in mud or sand and have valves (the two pieces of the shell) of equal size. The oval valves, which cover ...

aluminum

(Encyclopedia)aluminum ălˌyo͞omĭnˈēəm [key], metallic chemical element; symbol Al; at. no. 13; at. wt. 26.98154; m.p. 660.37℃; b.p. 2,467℃; sp. gr. 2.6989 at 20℃; valence +3. Aluminum is a silver-white...

wood

(Encyclopedia) CE5 Wood A. Cross section of a woody stem B. Enlarged view, showing xylem, phloem, and cambium wood, botanically, the xylem tissue that forms the bulk of the stem of a woody plant. Xylem conducts ...

matter

(Encyclopedia)matter, anything that has mass and occupies space. Matter is sometimes called koinomatter (Gr. koinos=common) to distinguish it from antimatter, or matter composed of antiparticles. The atomic th...

dolphin, aquatic mammal

(Encyclopedia)dolphin, aquatic mammal, any of the small toothed whales of the family Delphinidae, numbering more than 50 species. These include the true, or beaked, dolphins, the killer whale, the pilot whale, and ...

mental retardation

(Encyclopedia)mental retardation, below average level of intellectual functioning, usually defined by an IQ of below 70 to 75, combined with limitations in the skills necessary for daily living. Daily living skills...
 

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