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arc

(ärk)

1. Something shaped like a curve or arch: the vivid arc of a rainbow.

2. Mathematics A segment of a circle.

3. An electric arc.

4. Astronomy The apparent path of a celestial body as it rises above and falls below the horizon.

5. A progression of events suggesting narrative cohesion, especially one that rises to a climax and settles to a final conclusion.

intr.v. arced (ärkt), arc·ing (ärkĭng), arcs

1. To form an arc.

2. To move or seem to move in a curved path: the stars that arc across the sky.

[Middle English ark, from Old French arc, from Latin arcus.]

ARC

abbr.

1. AIDS-related complex

2. American Red Cross

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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