Columbia Encyclopedia
Search results
500 results found
coral
(Encyclopedia)coral, small, sedentary marine animal, related to the sea anemone but characterized by a skeleton of horny or calcareous material. The skeleton itself is also called coral. Although most corals form c...metamorphism
(Encyclopedia)metamorphism, in geology, process of change in the structure, texture, or composition of rocks caused by agents of heat, deforming pressure, shearing stress, hot, chemically active fluids, or a combin...clam
(Encyclopedia)clam, common name for certain bivalve mollusks, especially for marine species that live buried in mud or sand and have valves (the two pieces of the shell) of equal size. The oval valves, which cover ...sunspots
(Encyclopedia)sunspots, dark, usually irregularly shaped spots on the sun's surface that are actually solar magnetic storms. The spots are darker because the temperature of the spots is lower than that of the surro...Wittgenstein, Ludwig Josef Johann
(Encyclopedia)Wittgenstein, Ludwig Josef Johann loŏtˈvĭkh yōˈzĕf yōˈhän vĭtˈgənshtīn [key], 1889–1951, Austrian philosopher, b. Vienna. The second phase of Wittgenstein's philosophy commenced with ...radar
(Encyclopedia)radar, system or technique for detecting the position, movement, and nature of a remote object by means of radio waves reflected from its surface. Although most radar units use microwave frequencies, ...calligraphy
(Encyclopedia)calligraphy kəlĭgˈrəfē [key] [Gr.,=beautiful writing], skilled penmanship practiced as a fine art. See also inscription; paleography. The art of calligraphy is also practiced with the limited l...synthetic elements
(Encyclopedia)synthetic elements, in chemistry, radioactive elements that were not discovered occurring in nature but as artificially produced isotopes. They are technetium (at. no. 43), which was the first element...Avicenna
(Encyclopedia)Avicenna ăvĭsĕnˈə [key], Arabic Ibn Sina, 980–1037, Islamic philosopher and physician, of Persian origin, b. near Bukhara. He was the most renowned philosopher of medieval Islam and the most in...Afrikaans
(Encyclopedia)Afrikaans ăfˌrəkänsˈ [key], member of the West Germanic group of the Germanic subfamily of the Indo-European family of languages (see Germanic languages). Although its classification is still dis...Browse by Subject
- Earth and the Environment +-
- History +-
- Literature and the Arts +-
- Medicine +-
- People +-
- Philosophy and Religion +-
-
Places
+-
- Africa
- Asia
- Australia and Oceania
- Britain, Ireland, France, and the Low Countries
- Commonwealth of Independent States and the Baltic Nations
- Germany, Scandinavia, and Central Europe
- Latin America and the Caribbean
- Oceans, Continents, and Polar Regions
- Spain, Portugal, Italy, Greece, and the Balkans
- United States, Canada, and Greenland
- Plants and Animals +-
- Science and Technology +-
- Social Sciences and the Law +-
- Sports and Everyday Life +-
