That which stands in the way, or opposes; anything that hinders progress; a hindrance; an obstruction, physical or moral.

All fixed (whether temporary or permanent) and mobile objects, or parts thereof, that are located on an area intended for the surface movement of aircraft or that extend above a defined surface intended to protect aircraft in flight. abbreviation: OBST also called: obstruction Fr: obstacle

Obstruction or hindrance that interrupts dog's scenting. May be natural or man-made and dog and/or handler may have to go around, over or through it. (Ganz & Boyd)

something immaterial that stands in the way and must be circumvented or surmounted; "lack of immagination is an obstacle to one's advancement"; "the poverty of a district is an obstacle to good education"; "the filibuster was a major obstruction to the success of their plan"

That which interferes with the character's achievement of his/her goal.

A dramatic hurdle the protagonist must confront in order to accomplish his mission.

an internal or external circumstance which blocks a character from easily achieving his/her goals

a reason why a goal failed

Any barrier-natural or artificial-that stops or impedes the movement of a unit.

Any feature of the course that may impede a player's stance or kicking motion.

Any feature of the course that may impede any aspect of play.

In show jumping and the three-day event, an object a horse must clear to complete the course, such as a fence, gate or water jump.