concur

American Heritage® Dictionary of the English Language, Fourth Edition

1. v. To be of the same opinion; agree: concurred on the issue of preventing crime. See Synonyms at assent.
2. v. To act together; cooperate.
3. v. To occur at the same time; coincide: icy sleet that concurred with a forceful wind.
4. v. Obsolete To converge; meet.

Century Dictionary and Cyclopedia

1. To run together; meet in a point in space.
2. To come together or be accordant, as in character, action, or opinion; agree; coincide: followed by with before the person or thing and in before the object of concurrence.
3. To unite; combine; be associated: as, many causes concurred in bringing about his fall.
4. Eccles., to fall on two consecutive days, as two feasts. See concurrence, 4.
5. To assent: with to.
6. In law, to assert, with other claimants, a claim against the estate of an insolvent.
7. In English law, to unite in two or more persons the title to a single estate.
8. n. In mod. geom., the straight determined by two coplanar flat pencils.

Wiktionary

1. v. To unite or agree (in action or opinion); to have a common opinion; to coincide; to correspond.
2. v. To meet in the same point; to combine or conjoin; to contribute or help towards a common object or effect.
3. v. obsolete To run together; to meet.

GNU Webster's 1913

1. v. obsolete To run together; to meet.
2. v. To meet in the same point; to combine or conjoin; to contribute or help toward a common object or effect.
3. v. To unite or agree (in action or opinion); to join; to act jointly; to agree; to coincide; to correspond.
4. v. obsolete To assent; to consent.

WordNet 3.0

1. v. be in accord; be in agreement
2. v. happen simultaneously