cen·ter /ˈsɛntɚ/ 名詞
中心; 齊中; 中央
1. A point equally distant from the extremities of a line, figure, or body, or from all parts of the circumference of a circle; the middle point or place.
2. The middle or central portion of anything.
3. A principal or important point of concentration; the nucleus around which things are gathered or to which they tend; an object of attention, action, or force; as, a center of attraction.
4. The earth. [Obs.]
5. Those members of a legislative assembly (as in France) who support the existing government. They sit in the middle of the legislative chamber, opposite the presiding officer, between the conservatives or monarchists, who sit on the right of the speaker, and the radicals or advanced republicans who occupy the seats on his left, See Right, and Left.
6. Arch. A temporary structure upon which the materials of a vault or arch are supported in position until the work becomes self-supporting.
7. Mech. (a) One of the two conical steel pins, in a lathe, etc., upon which the work is held, and about which it revolves. (b) A conical recess, or indentation, in the end of a shaft or other work, to receive the point of a center, on which the work can turn, as in a lathe.
Note: ☞ In a lathe the live center is in the spindle of the head stock; the dead center is on the tail stock. Planer centers are stocks carrying centers, when the object to be planed must be turned on its axis.
Center of an army, the body or troops occupying the place in the line between the wings.
Center of a curve or Center of a surface Geom. (a) A point such that every line drawn through the point and terminated by the curve or surface is bisected at the point. (b) The fixed point of reference in polar coordinates. See Coordinates.
Center of curvature of a curve Geom., the center of that circle which has at any given point of the curve closer contact with the curve than has any other circle whatever. See Circle.
Center of a fleet, the division or column between the van and rear, or between the weather division and the lee.
Center of gravity Mech., that point of a body about which all its parts can be balanced, or which being supported, the whole body will remain at rest, though acted upon by gravity.
Center of gyration Mech., that point in a rotating body at which the whole mass might be concentrated (theoretically) without altering the resistance of the intertia of the body to angular acceleration or retardation.
Center of inertia Mech., the center of gravity of a body or system of bodies.
Center of motion, the point which remains at rest, while all the other parts of a body move round it.
Center of oscillation, the point at which, if the whole matter of a suspended body were collected, the time of oscillation would be the same as it is in the actual form and state of the body.
Center of percussion, that point in a body moving about a fixed axis at which it may strike an obstacle without communicating a shock to the axis.
Center of pressure Hydros., that point in a surface pressed by a fluid, at which, if a force equal to the whole pressure and in the same line be applied in a contrary direction, it will balance or counteract the whole pressure of the fluid.
Cen·ter, Cen·tre v. i. [imp. & p. p. Centered or Centred p. pr. & vb. n. Centering or Centring.]
1. To be placed in a center; to be central.
2. To be collected to a point; to be concentrated; to rest on, or gather about, as a center.
Where there is no visible truth wherein to center, error is as wide as men's fancies. --Dr. H. More.
Our hopes must center in ourselves alone. --Dryden.
Cen·ter , Cen·tre v. t.
1. To place or fix in the center or on a central point.
2. To collect to a point; to concentrate.
Thy joys are centered all in me alone. --Prior.
3. Mech. To form a recess or indentation for the reception of a center.
adj 1: equally distant from the extremes [syn: center(a), halfway,
2: of or belonging to neither the right nor the left
politically or intellectually [ant: right, left]
n 1: an area that is approximately central within some larger
region; "it is in the center of town"; "they ran forward
into the heart of the struggle"; "they were in the eye
of the storm" [syn: centre, middle, heart, eye]
2: the piece of ground in the outfield directly ahead of the
catcher; "he hit the ball to deep center" [syn: center
3: a building dedicated to a particular activity; "they were
raising money to build a new center for research" [syn: centre]
4: a point equidistant from the ends of a line or the
extremities of a figure [syn: centre, midpoint]
5: the choicest or most essential or most vital part of some
idea or experience; "the gist of the prosecutor's
argument"; "the heart and soul of the Republican Party";
"the nub of the story" [syn: kernel, substance, core,
essence, gist, heart, heart and soul, inwardness,
marrow, meat, nub, pith, sum, nitty-gritty]
6: the object upon which interest and attention focuses; "his
stories made him the center of the party" [syn: center of
7: a cluster of nerve cells governing a specific bodily
process; "in most people the speech center is in the left
hemisphere" [syn: centre, nerve center, nerve centre]
8: the middle of a military or naval formation; "they had to
reinforce the center"
9: (basketball) the person who plays center on a basketball
10: (football) the person who plays center on the line of
scrimmage and snaps the ball to the quarterback; "the
center fumbled the handoff" [syn: snapper]
11: a place where some particular activity is concentrated;
"they received messages from several centers" [syn: centre]
12: politically moderate persons; centrists
13: (ice hockey) the person who plays center on a hockey team
14: the sweet central portion of a piece of candy that is
enclosed in chocolate or some other covering [syn: centre]
15: mercantile establishment consisting of a carefully
landscaped complex of shops representing leading
merchandisers; usually includes restaurants and a
convenient parking area; a modern version of the
traditional marketplace; "a good plaza should have a
movie house"; "they spent their weekends at the local
malls" [syn: plaza, mall, shopping mall, shopping
center, shopping centre]
16: the position on a hockey team of the player who participates
in the face off at the beginning of the game
17: the position of the player on the line of scrimmage who puts
the ball in play; "it is a center's responsibility to get
the football to the quarterback"
18: a position on a basketball team of the player who
participates in the center jump to start the game
v 1: center upon; "Her entire attention centered on her
children"; "Our day revolved around our work" [syn: focus
on, center on, revolve around, revolve about, concentrate
2: direct one's attention on something; "Please focus on your
studies and not on your hobbies" [syn: concentrate, focus,
centre, pore, rivet]
3: move into the center; "That vase in the picture is not
centered" [syn: centre]