NOTE: implies an existing thing or situation, not a specific action (see Sense 2)
NOTE: usually refers to the one who must confront the obstacle
John drove carefully around the obstruction in the middle of the road.
Bars on windows are effective obstructions to home intruders.
His basic insecurity has been an obstruction to getting a better job. (figurative)
NOTE: implies an agent performing an action
NOTE: refers to the one creating a hindrance or obstacle
They will use the filibuster as an obstruction to getting the bill passed. (political act)
His destruction of the evidence is interpreted as an obstruction of justice.
The referee gave a penalty to the player for his obstruction of the ball.
WordNet 3.0 Sense Numbers: 4, 5
The doctor determined the patient had an obstruction in the lower intestines.
Before attempting mouth-to-mouth resuscitation, remove any obstructions from the victim's throat.
Chicken bones can create obstructions in dogs' bowels.
WordNet 3.0 Sense Numbers: 2