The Collaborative International Dictionary of English v.0.48:

Center \Cen"ter\, Centre \Cen"tre\ v. i. [imp. & p. p.
   Centered or Centred (s[e^]n"t[~e]rd); p. pr. & vb. n.
   Centering or Centring.]
   1. To be placed in a center; to be central.
      [1913 Webster]

   2. To be collected to a point; to be concentrated; to rest
      on, or gather about, as a center.
      [1913 Webster]

            Where there is no visible truth wherein to center,
            error is as wide as men's fancies.    --Dr. H. More.
      [1913 Webster]

            Our hopes must center in ourselves alone. --Dryden.
      [1913 Webster] Center

The Collaborative International Dictionary of English v.0.48:

Centering \Cen"ter*ing\, n. (Arch.)
   Same as Center, n., 6. [Written also centring.]
   [1913 Webster] Centerpiece

WordNet (r) 3.0 (2006):

centering
    n 1: the concentration of attention or energy on something; "the
         focus of activity shifted to molecular biology"; "he had no
         direction in his life" [syn: focus, focusing,
         focussing, focal point, direction, centering]
    2: (American football) putting the ball in play by passing it
       (between the legs) to a back; "the quarterback fumbled the
       snap" [syn: centering, snap]