well-understood
21mathematics — /math euh mat iks/, n. 1. (used with a sing. v.) the systematic treatment of magnitude, relationships between figures and forms, and relations between quantities expressed symbolically. 2. (used with a sing. or pl. v.) mathematical procedures,… …
22cardiovascular disease — Introduction any of the diseases, whether congenital or acquired, of the heart and blood vessels (blood vessel). Among the most important are atherosclerosis, rheumatic heart disease, and vascular inflammation. Cardiovascular diseases are a …
23Masonry (Freemasonry) — Masonry (Freemasonry) † Catholic Encyclopedia ► Masonry (Freemasonry) The subject is treated under the following heads: I. Name and Definition; II. Origin and Early History; III. Fundamental Principles and Spirit; IV.… …
24Seventeenth-century materialism: Gassendi and Hobbes — T.Sorell In the English speaking world Pierre Gassendi is probably best known as the author of a set of Objections to Descartes’s Meditations. These Objections, the fifth of seven sets collected by Mersenne, are relatively long and full, and… …
25astronomy — /euh stron euh mee/, n. the science that deals with the material universe beyond the earth s atmosphere. [1175 1225; ME astronomie ( < AF) < L astronomia < Gk. See ASTRO , NOMY] * * * I Science dealing with the origin, evolution, composition,… …
26Egypt, ancient — Introduction civilization in northeastern Africa dating from the 3rd millennium BC. Its many achievements, preserved in its art and monuments, hold a fascination that continues to grow as archaeological finds expose its secrets. This article… …
27endocrine system, human — ▪ anatomy Introduction group of ductless glands (gland) that regulate body processes by secreting chemical substances called hormones (hormone). Hormones act on nearby tissues or are carried in the bloodstream to act on specific target organs… …
28nervous system, human — ▪ anatomy Introduction system that conducts stimuli from sensory receptors to the brain and spinal cord and that conducts impulses back to other parts of the body. As with other higher vertebrates, the human nervous system has two main… …
29Representation theory — This article is about the theory of representations of algebraic structures by linear transformations and matrices. For the more general notion of representations throughout mathematics, see representation (mathematics). Representation theory is… …
30glacier — glaciered, adj. /glay sheuhr/, n. an extended mass of ice formed from snow falling and accumulating over the years and moving very slowly, either descending from high mountains, as in valley glaciers, or moving outward from centers of… …
