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That which has a common center with something else. Its pecular relations to its concentrics. Coleridge.

Having a common center, as circles of different size, one within another. Concentric circles upon the surface of the water. Sir I. Newton. Concentrical rings like those of an onion. Arbuthnot.

In a concentric manner.

The state of being concentric.

A burner consisting of two or more concentric Argand burners (the inner rising above the outer) and a central tube by which oxygen gas or common air is supplied.

own color, and brilliant adamantine luster; also massive, sometimes in compact forms with concentric fibrous structure resembling wood (wood tin), also in rolled fragments or pebbly (Stream tin). It is the chief source of metallic tin. See Black tin, under Black.

A circle; a concentric layer. [Obs.] "The circinations and spherical rounds of onions." Sir T. Browne.

Consisting of a series of parallel cones, each made up of many concentric cones closely packed together; -- said of a kind of structure sometimes observed in sedimentary rocks.

The area inclosed between two concentric perimeters.

pertaining to the Cycloidei. Cycloid scale (Zoöl.), a fish scale which is thin and shows concentric lines of growth, without serrations on the margin.

either in whole or in part, as to area or volume, have not the same center; -- opposed to concentric.

orm of conductor, designed by Ferranti, for currents of high potential, and consisting of concentric tubes of copper separated by an insulating material composed of paper saturated with black mineral wax.

thus, a section of a uniaxial crystal, cut normal to the vertical axis, shows a series of concentric colored rings with a single black cross; -- so called because produced by the interference of luminous waves. -- Interference fringe. (Optics) See Fringe.

Friedrich Krupp, at Essen in Prussia. Guns of over eight-inch bore are made up of several concentric cylinders; those of a smaller size are forged solid. Knight.

A spherulitic cavity often with concentric chambers, observed in some volcanic rocks, as in rhyolitic lavas. It is supposed to be produced by expanding gas, whence the name.

Native hydrous carbonate of copper, usually occurring in green mammillary masses with concentric fibrous structure.

cuts the teeth at about the middle of their height, and, in a circular gear, is a circle concentric with the axis of the gear; the line, or circle, on which the pitch of teeth is measured. -- Pitch of a roof (Arch.), the inclination or slope of the sides expressed by the height in parts of the span; as, one half pitc…

In the Ptolemaic system, the outermost of the revolving concentric spheres constituting the universe, the motion of which was supposed to carry with it all the inclosed spheres with their planets in a daily revolution from east to west. See Crystalline heavens, under Crystalline. The motions of the greatest persons in…

A bow or arch exhibiting, in concentric bands, the several colors of the spectrum, and formed in the part of the hemisphere opposite to the sun by the refraction and reflection of the sun's rays in drops of falling rain.

The plane figure included between the circumferences of two concentric circles.