EVOLUTION

n. Esv-o-lu2'shu'n. Lat., evolutio (from evolvere, to unroll). Fr., evolution. Ger., Entwickelung. It.,evoluzione. Sp., evolucion, desnrrollo. 1. The gradual development of an organism or of one or more of its parts. 2. Of Darwin and others, the supposed proce of gradual change by which new species arise and low organisms are converted into higher ones in the course of long periods of time. 3. Of the uterus, its growth and development during pregnancy (the opposite of involution}. 4. In chemistry, the gradual liberation of a substance (e. g., a gas) from U, blue; U3, lull; U4, full; U6, urn; U6, like u (German). [s. 779]