Columbia Encyclopedia

Search results

500 results found

nautilus, in zoology

(Encyclopedia)nautilus or chambered nautilus, cephalopod mollusk belonging to the sole surviving genus (Nautilus) of a subclass that flourished 200 million years ago, known as the nautiloids. The spirally coiled sh...

aureole, in art

(Encyclopedia)aureole, in art: see nimbus.

aureole, in physics

(Encyclopedia)aureole ôrˈēōlˌ [key], in physics, luminous circle seen when the sun or other bright light is observed through a diffuse medium, i.e., smoke, thin cloud, fog, haze, or mist. It sometimes occurs a...

orders in council

(Encyclopedia)orders in council, in British government, orders given by the sovereign on the advice of all or some of the members of the privy council, without the prior consent of Parliament. Orders in council, fi...

Neptune, in astronomy

(Encyclopedia)Neptune, in astronomy, 8th planet from the sun at a mean distance of about 2.8 billion mi (4.5 billion km) with an orbit lying between those of Uranus and the dwarf planet Pluto; its period of revolut...

Orion, in astronomy

(Encyclopedia)Orion, in astronomy, constellation located on the celestial equator. It is one of the most conspicuous and easily recognizable constellations in the entire sky. From ancient times it has been mentione...

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...

Vulcan, in astronomy

(Encyclopedia)Vulcan, in astronomy, hypothetical planet whose existence was proposed by Le Verrier to explain part of the advance of the perihelion of Mercury, not all of which could be accounted for by gravitation...