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brake, in technology

(Encyclopedia)CE5 Shoe brake CE5 Disk brake brake, in technology, device to slow or stop the motion of a mechanism or vehicle. The vacuum brake system, or vacuum brake, depends upon the use of a vacuum to ...

Vesta, in astronomy

(Encyclopedia)Vesta vĕsˈtə [key], in astronomy, the fourth asteroid to be discovered. It was found in 1807 by H. Olbers. It is the third largest asteroid in size, with a diameter of c.326 mi (525 km). Its averag...

voice, in grammar

(Encyclopedia)voice, grammatical category according to which an action is referred to as done by the subject (active, e.g., men shoot bears) or to the subject (passive, e.g., bears are shot by men). In Latin, voice...

aids, in feudalism

(Encyclopedia)aids, in feudalism, type of feudal due paid by a vassal to his suzerain (overlord). Aids varied with time and place, although in English-speaking countries aids were traditionally due on the knighting...

AIDS, in medicine

(Encyclopedia)AIDS or acquired immunodeficiency syndrome, fatal disease caused by a rapidly mutating retrovirus that attacks the immune system and leaves the victim vulnerable to infections, malignancies, and neuro...

Cassiopeia, in astronomy

(Encyclopedia)Cassiopeia, in astronomy, prominent northern constellation located almost directly opposite the Big Dipper across the north celestial pole. Five bright stars in the constellation form a rough W (or M)...

Castor, in astronomy

(Encyclopedia)Castor kăsˈtər [key], bright star in the constellation Gemini; Bayer designation α Geminorum; 1992 position R.A. 7h34.1m, Dec. +31°54′. Slightly dimmer than Pollux, with which it forms the Twin...

category, in philosophy

(Encyclopedia)category, philosophical term that literally means predication or assertion. It was first used by Aristotle, whose 10 categories formed a list of all the ways in which assertions can be made of a subje...

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