What term describes something that acts as an obstacle or discouragement?

The term that describes something that acts as an obstacle or discouragement is "deterrent." A deterrent is specifically something that prevents or discourages an action or behavior, often by instilling fear or doubt regarding the consequences. This could encompass a variety of situations, such as a law that deters crime or a challenging task that discourages individuals from pursuing it.

Encouragement, on the other hand, is about providing support and motivation, which is the opposite of creating an obstacle. A motive is related to a reason for doing something, typically inspiring action rather than discouraging it. Inspiration similarly relates to providing positive stimulation and enthusiasm to pursue goals. Therefore, among these terms, "deterrent" is the most accurate in describing an obstacle or discouragement.