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aconite

(Encyclopedia)aconite ăkˈənīt [key], monkshood, or wolfsbane, any of several species of the genus Aconitum of the family Ranunculaceae (buttercup family), hardy perennial plants of the north temperate zone, gro...

thrombolytic drug

(Encyclopedia)thrombolytic drug thrŏmˌbəlĭtˈĭk [key] or clot-dissolving drug, substance, such as streptokinase or tissue plasminogen activator (tPA), that causes the breakdown of blood clots (see thrombosis) ...

potassium carbonate

(Encyclopedia)potassium carbonate, chemical compound, K2CO3, white, crystalline, deliquescent substance that forms a strongly alkaline water solution. It is available commercially as a white, granular powder common...

button

(Encyclopedia)button, knoblike appendage used on wearing apparel either for ornament or for fastening. Although buttons were sometimes used as fasteners by Greeks and Romans, they were more often merely ornamental ...

phenolphthalein

(Encyclopedia)phenolphthalein fēˈnôlthălˈēən [key], or 2,2-Bis(p-hydroxyphenyl) phthalide, C20H14O4, crystalline organic compound. It is used medicinally as a laxative and is widely employed in the laborator...

metamorphism

(Encyclopedia)metamorphism, in geology, process of change in the structure, texture, or composition of rocks caused by agents of heat, deforming pressure, shearing stress, hot, chemically active fluids, or a combin...

Fleming, Sir Alexander

(Encyclopedia)Fleming, Sir Alexander, 1881–1955, Scottish bacteriologist, discoverer of penicillin (1928) and lysozyme (1922), an antibacterial substance found in saliva and other body secretions. Educated at St....

dwarf tree

(Encyclopedia)dwarf tree, in horticultural practice, a tree artificially kept to a smaller size than is normal for average members of the species. This is usually accomplished either by limiting its root space and ...

Cairngorms

(Encyclopedia)Cairngorms kârngôrmzˈ, kârnˈgôrmz [key], group of mountains forming part of the Grampian Mts, in Highland, Moray, and Aberdeenshire, central Scotland, between the Dee and the upper Spey rivers; ...

agronomy

(Encyclopedia)agronomy əgrŏnˈəmē [key], branch of agriculture dealing with various physical and biological factors—including soil management, tillage, crop rotation, breeding, weed control, and climate—rel...