Noah Webster's New International Dictionary of the English Language

1. (n.) A meeting or coming together; agreement; union; conjunction; combination.

2. (n.) A meeting of minds; agreement in opinion; union in design or act; -- implying joint approbation.

3. (n.) Agreement or consent, implying aid or contribution of power or influence; cooperation.

4. (n.) A common right; coincidence of equal powers; as, a concurrence of jurisdiction in two different courts.