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con·cen·ter

(kən-sĕntər, 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.]

Indo-European & Semitic Roots Appendices

Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

Indo-European Roots

Semitic Roots

The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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