con·cen·ter 
(kən-sĕntər, kŏn-)
(kən-sĕntər, kŏn-)tr. & intr.v. con·cen·tered, con·cen·ter·ing, con·cen·ters
To direct toward or come together at a common center.
[Probably Italian concentrare or French concentrer : both from Latin com-, com- + Latin centrum, center; see CENTER.]