a.

1. 同时发生的
   Concurrent with the American military maneuvers in the South China Sea is the State Department's declaration of its resolve to maintain navigation rights.

   与美国在南海的军事行动同时发生的是美国国务院对维持海上航行权的声明。

2. 赞同的；协力的；一致的
3. 【律】同等权力的
4. 【数】共点的

n.

1. 同时发生的状况
2. 【数】共点

adj.

1. existing or happening at the same time.
2. agreeing or consistent.
3. Mathematics  (of three or more lines) meeting at or tending towards one point.