river — river1 riverless, adj. riverlike, adj. /riv euhr/, n. 1. a natural stream of water of fairly large size flowing in a definite course or channel or series of diverging and converging channels. 2. a similar stream of something other than water: a… … Universalium
2 × 2 real matrices — The set of 2 × 2 real matrices is denoted by M(2, R). Two matrices p and q in M(2, R) have a sum p + q given by matrix addition. The product matrix p q is formed from the dot product of the rows and columns of its factors… … Wikipedia
Natural language — This article is about natural language in neuropsychology and linguistics. For natural language in computer systems, see Natural language processing. Neuropsychology … Wikipedia
geography — /jee og reuh fee/, n., pl. geographies. 1. the science dealing with the areal differentiation of the earth s surface, as shown in the character, arrangement, and interrelations over the world of such elements as climate, elevation, soil,… … Universalium
Comparative method — This article is about the comparative method in linguistics. For other kinds of comparative methods, see Comparative (disambiguation). Linguistic map representing a Tree model of the Romance languages based on the comparative method. Here the… … Wikipedia
Latitudinal gradients in species diversity — The pattern= The increase in species richness or biodiversity that occurs from the poles to the tropics, often referred to as the latitudinal gradient in species diversity, is one of the most widely recognized patterns in ecology. Put another way … Wikipedia
Hekla — Höhe 1.491 m … Deutsch Wikipedia
Proto-Algonquian language — Proto Algonquian (commonly abbreviated PA) is the name given to the posited proto language of the languages of the Algonquian family. One theory, first put forth by Frank Siebert in 1967, is that it was spoken between 2500 and 3000 years ago… … Wikipedia
Kaapvaal craton — The Kaapvaal craton (Limpopo province of South Africa), along with the Pilbara craton of Western Australia, are the only remaining areas of pristine 3.6 2.5 Ga crust on Earth. Similarities of rock records from both these cratons, especially of… … Wikipedia
oil shale — Geol. a black or dark brown shale or siltstone rich in bitumens, from which shale oil is obtained by destructive distillation. [1870 75] * * * Any fine grained sedimentary rock that contains solid organic matter (kerogen) and yields significant… … Universalium
Earth Sciences — ▪ 2009 Introduction Geology and Geochemistry The theme of the 33rd International Geological Congress, which was held in Norway in August 2008, was “Earth System Science: Foundation for Sustainable Development.” It was attended by nearly… … Universalium