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fluoridation

(Encyclopedia)fluoridation flo͝orˌĭdāˈshən [key], process of adding a fluoride to the water supply of a community to preserve the teeth of the inhabitants. Tooth enamel ordinarily contains small amounts of fl...

peyote

(Encyclopedia)peyote pāōˈtē [key], spineless cactus (Lophophora williamsii), ingested by indigenous people in Mexico and the United States to produce visions. The plant is native to the SW United States, partic...

methyl

(Encyclopedia)methyl mĕthˈəl [key], CH3, organic free radical or alkyl group derived from methane by the removal of one hydrogen atom. ...

phenyl

(Encyclopedia)phenyl fĕnˈəl [key], C6H5, organic free radical or alkyl group derived from benzene by removing one hydrogen atom. ...

polyester

(Encyclopedia)polyester, synthetic fiber, produced by the polymerization of the product formed when an alcohol and organic acid react. The outstanding characteristic of polyesters is their ability to resist wrinkli...

vulcanization

(Encyclopedia)vulcanization vŭlˌkənəzāˈshən [key], treatment of rubber to give it certain qualities, e.g., strength, elasticity, and resistance to solvents, and to render it impervious to moderate heat and c...

siderite

(Encyclopedia)siderite kălˈĭbīt [key], a mineral, varying in color from brown, green, or gray to black and occurring in nature in massive and crystalline form. A carbonate of iron, FeCO3, it serves as an iron o...

cryolite

(Encyclopedia)cryolite or kryolite both: krīˈəlītˌ [key] [Gr.,=frost stone], mineral usually pure white or colorless but sometimes tinted in shades of pink, brown, or even black and having a luster like that o...

rutile

(Encyclopedia)rutile, mineral, one of three forms of titanium dioxide (TiO2; see titanium). It occurs in crystals, often in twins or rosettes, and is typically brownish red, although there are black varieties. Ruti...

cobaltite

(Encyclopedia)cobaltite kōˈbôltīt, kōbôlˈtīt [key], opaque, silver-white, sometimes reddish or grayish mineral of the pyrite group, a compound of cobalt, arsenic, and sulfur, CoAsS. It occurs in crystals of...