(sen′tər) noun
1. Geom. a The point within a circle or sphere equally distant from any point on the circumference or surface. b The point within a regular polygon equidistant from the vertices.
2. The middle: the center of the town.
3. The point, object, or place about which things cluster or to which they converge.
4. A fixed point or line about which a thing or things revolve; point of attraction or convergence; focal point: the center of interest.
5. The point of divergence, emanation, or radiation; nucleus; origin.
6. The earth considered as the center of the universe; the center of the earth.
7. The part of a target nearest the bull's-eye, or a shot striking this part.
8. The middle part of an army in order of battle, occupying the front between the wings.
9. Mech. a One of two conical points, as in a lathe, between which an object is held and rotated on an axial line. The one at the end from which the object is rotated is the live center, the other the dead center. b The depression in a piece of revolving work, as a shaft, into which the conical point enters to support it.
10. The person who takes the middle position of the forward line in many athletic games, as football, basketball, etc.
11. Any place considered the hub of a specific activity: a manufacturing center.
—v.t.
1. To place in the center.
2. To supply with a center.
3. To draw or converge in one place; concentrate.
4. In football, to pass the ball from the line to a back-field player.
5. To determine the center of; shape a lens so as to have it thickest in the center.
—v.i.
6. To be in or at the center; have a focal point: The riots centered in the industrial section of the city.
7. To gather or converge, as toward a center: The crowds centered in the square.
—adjective Central; middle. Also spelled centre. [<L centrum <Gk. kentron point (i.e., around which a circle is described)] Synonyms (noun): middle, midst. We speak of the center of a circle, the middle of a room or the street. The center is equally distant from every point of the circumference of a circle, or from the opposite boundaries on each axis of a parallelogram, etc.; middle is more general and less definite. The center is a point; the middle may be a line or a space. We say at the center; in the middle. Midst commonly implies a group or multitude of surrounding objects. Compare synonyms for AMID. Antonyms: bound, boundary, circumference, perimeter, rim.

(sen′tər) noun
In some European legislatures, the members sitting on the middle benches, a position generally assigned to those of moderate views: also spelled Centre.