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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...

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....

hematite

(Encyclopedia)hematite hĕmˈətīt [key], mineral, an oxide of iron, Fe2O3, containing about 70% metal, occurring in nature in red to reddish-brown earthy masses and in steel-gray to black crystalline forms. Hemat...

chloroprene

(Encyclopedia)chloroprene klōrˈəprēnˌ [key] or 2-chloro-1,3-butadiene, colorless liquid organic compound used in the synthesis of neoprene and certain other rubbers. The structure of the chloroprene molecule i...

iridescence

(Encyclopedia)iridescence ĭrˌədĕsˈəns [key], exhibition of rainbowlike colors on a surface. It usually results from interference when light composed of different wavelengths is reflected from the superficial ...

solvent

(Encyclopedia)solvent, constituent of a solution that acts as a dissolving agent. In solutions of solids or gases in a liquid, the liquid is the solvent. In all other solutions (i.e., liquids in liquids or solids i...

ambergris

(Encyclopedia)ambergris ămˈbərgrēs [key], waxlike substance originating as a morbid concretion in the intestine of the sperm whale. Lighter than water, it is found floating on tropical seas or cast up on the sh...

sodium thiosulfate

(Encyclopedia)sodium thiosulfate, Na2S2O3, colorless crystalline compound that is more familiar as the pentahydrate, Na2S2O3·5H2O, an efflorescent, monoclinic crystalline substance also called sodium hyposulfite o...