n.

1. 阻礙，妨礙；阻塞[U]
2. 阻塞物；障礙[C]
   These obstructions could take some weeks to clear from these canals.

   這些障礙物可能要花幾週時間才能從運河中清除掉。

n.

1. the action of obstructing or the state of being obstructed.
2. a thing that obstructs.