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geologic timescale

(Encyclopedia)CE5 geologic timescale, a chronological scale of earth's history used to measure the relative or absolute age of any part of geologic time. Of the numerous timescales, the most common is based on g...

American Academy and Institute of Arts and Letters

(Encyclopedia)American Academy and Institute of Arts and Letters, honorary academy of notable American artists, writers, and composers. The National Institute of Arts and Letters, founded in 1898, served as the par...

decimal system

(Encyclopedia)decimal system [Lat.,=of tenths], numeration system based on powers of 10. A number is written as a row of digits, with each position in the row corresponding to a certain power of 10. A decimal point...

Mesozoic era

(Encyclopedia)Mesozoic era mĕzˌəzōˈĭk [key] [Gr.,=middle life], major division of geologic time (see Geologic Timescale, tablegeologic timescale, table) from 65 to 225 million years ago. Great crustal disturb...

clock

(Encyclopedia)CE5 A pendulum clock: Weight-driven clock mechanism clock, instrument for measuring and indicating time. Predecessors of the clock were the sundial, the hourglass, and the clepsydra. See also watc...

spraying

(Encyclopedia)spraying, horticultural practice of applying fungicides, insecticides, and herbicides, usually in solution, to plants. It may be accomplished by various means, e.g., the watering can, sprinkler attach...

cirrhosis

(Encyclopedia)cirrhosis sərōˈsəs [key], degeneration of tissue in an organ resulting in fibrosis, with nodule and scar formation. The term is most often used in relation to the liver, because that organ is most...

coronavirus

(Encyclopedia)coronavirus, any of a group (family Coronaviridae, subfamily Orthocoronavirinae) of enveloped single-stranded RNA viruses that have a crownlike or sunlike appearance under an electron microscope due t...

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