A term referring to the lamp and ballast combination, and sometimes to the entire lighting delivery system including the fixture, the optics, the particular layout and the ...
A class of substances (usually proteins) that are produced by specialized cells and that travel to other parts of the body, where they influence chemical reactions and regulate ...
Form of sociopolitical organization usually based on horticulture or pastoralism. Socioeconomic stratification and centralized rule are absent in tribes, and there is no means of ...
Explanation that establishes a correlation or interrelationship between social customs. When customs are functionally interrelated, if one changes, the others also change.
1. A violently rotating column of air, in contact with the ground, either pendant from a cumuliform cloud or underneath a cumuliform cloud, and often ...
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