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tryptophan

(Encyclopedia)CE5 tryptophan trĭpˈtəfăn [key], organic compound, one of the 20 amino acids commonly found in animal proteins. Only the l-stereoisomer appears in mammalian protein. It is one of several essent...

sextant

(Encyclopedia)CE5 Sextant sextant, instrument for measuring the altitude of the sun or another celestial body; such measurements can then be used to determine the observer's geographical position or for other n...

phase, in astronomy

(Encyclopedia)CE5 Phases of the moon phase, in astronomy, the measure of how much of the illuminated surface of a planet or satellite can be seen from a point at a distance from that body; the term is most ofte...

capital, in architecture

(Encyclopedia)CE5 A. Types of capitals B. Parts of a capital capital, in architecture, the crowning member of a column, pilaster, or pier. It acts as the bearing member beneath the lintel or arch supported by t...

radio frequency

(Encyclopedia)radio frequency, range of electromagnetic waves with a frequency or wavelength suitable for communication uses. Some of these waves serve as carriers of the lower-frequency audio waves; others are mod...

balance

(Encyclopedia)balance, instrument used in laboratories and pharmacies to measure the mass or weight of a body. A balance functions by measuring the force of gravity that the earth exerts on an object, i.e., its wei...

radioactivity

(Encyclopedia)CE5 Effects of a magnetic field on the products of radioactivity CE5 Disintegration series: Radioactive decay of radium-226 into lead-206 radioactivity, spontaneous disintegration or decay of t...

charade

(Encyclopedia)charade shərādˈ [key], verbal, written, or acted representation of a word, its syllables, or a number of words. The object is to guess the idea being conveyed. Winthrop M. Praed wrote many of the w...

Norton, Joshua Abraham

(Encyclopedia)Norton, Joshua Abraham, 1818–80, colorful eccentric of San Francisco known as “Emperor Norton,” b. London. He went (1820) with his parents to Cape Town, South Africa, and news of the California ...

Leith

(Encyclopedia)Leith lēth [key], former town, Edinburgh, SE Scotland, on the south shore of the Firth of Forth. It was incorporated into Edinburgh in 1920. As a strategically located port, Leith was the object of c...