Webster's Revised Unabridged Dictionary · 1913

Concurrent

Concurrent , adjective

[French concurrent, Latin concurrens, present participle of concurrere.]

1.
Acting in conjunction; agreeing in the same act or opinion; contributing to the same event or effect; cooperating.
I join with these laws the personal presence of the kings' son, as a concurrent cause of this reformation. — Sir J. Davies
The concurrent testimony of antiquity. — Bp. Warburton
2.
Conjoined; associate; concomitant; existing or happening at the same time.
There is no difference the concurrent echo and the iterant but the quickness or slowness of the return. — Bacon
Changes... concurrent with the visual changes in the eye. — Tyndall
3.
Joint and equal in authority; taking cognizance of similar questions; operating on the same objects; as, the concurrent jurisdiction of courts.
4.
(Geometry) Meeting in one point.

Concurrent , noun

1.
One who, or that which, concurs; a joint or contributory cause.
To all affairs of importance there are three necessary concurrents... time, industry, and faculties. — Dr. H. More
2.
One pursuing the same course, or seeking the same objects; hence, a rival; an opponent.
Menander... had no concurrent in his time that came near unto him. — Holland
3.
(Chron.) One of the supernumerary days of the year over fifty-two complete weeks; -- so called because they concur with the solar cycle, the course of which they follow.