Centre

Center , sen′tėr, n. the middle point of anything, esp. a circle or sphere: the middle: the point toward which all things move or are drawn: the chief leader of an organisation—head-centre: the men of moderate political opinions in the French Chamber, sitting right in front of the president, with extreme men on the right and on the left—further subdivisions are Right-centre and Left-centre : the Ultramontane party in Germany.— v.t. to place on or collect to a centre.— v.i. to be placed in the middle:— pr.p. cen′tring, cen′tering; pa.p. cen′tred, cen′tered. — adj. Cen′tral , belonging to the centre, principal, dominant: belonging to a nerve-centre, of affections caused by injury to the brain or spinal cord.— ns. Central isā′tion , Cen′tralism , the tendency to administer by the sovereign or central government matters which would be otherwise under local management.— v.t. Cen′tralise , to draw to a centre.— n. Central′ity , central position.— advs. Cen′trally , Cen′trically .— ns. Cen′tre-bit , a joiner's tool, turning on a centre, for boring circular holes—one of the chief tools of the burglar; Cen′tre-board , a shifting keel, fitted to drop below and in line with the keel proper in order to increase or diminish the draught of a boat—much used in United States racing yachts; Cen′tre-piece , an ornament for the middle of a table, ceiling, .— adjs. Cen′tric , Cen′trical , relating to, placed in, or containing the centre.— ns. Cen′tricalne , Centric′ity ; Cen′trum , the body of a vertebra.— Central fire , said of a cartridge in which the fulminate is placed in the centre of the base, as opposed to rim fire ; Central forces , forces whose action is to cause a moving body to tend towards a fixed point called the centre of force.— Centre of attraction , the point to which bodies tend by the force of gravity; Centre of buoyancy , or displacement , the point in an immersed body at which the resultant vertical pre ure may be supposed to act; Centre of gravity , a certain point, invariably situated with regard to the body, through which the resultant of the attracting forces between the earth and its several molecules always pa es; Centre of inertia , or ma , the centre of a set of parallel forces acting on all the particles of a body, each force being proportional to the ma of the particle on which it acts; Centre of oscillation , the point in a body occupied by that particle which is accelerated and retarded to an equal amount, and which therefore moves as if it were a single pendulum unconnected with the rest of the body; Centre of percu ion , the point in which the direction of a blow, given to a body, intersects the plane in which the fixed axis and the centre of inertia lie, making the body begin to rotate about a fixed axis, without causing any pre ure on the axis; Centre of pre ure , the point at which the direction of a single force, which is equivalent to the fluid pre ure on the plane surface, meets the surface. [Fr.,—L. centrum —Gr. kentron , a sharp point.]