What is a synonym for "deterrent"?

A synonym for "deterrent" is "obstacle" because both terms convey the idea of something that prevents or hinders action. A deterrent is specifically designed to discourage or prevent certain behaviors or actions, often through fear of consequences or punitive measures. Similarly, an obstacle stands in the way of progress, making it harder to achieve a goal or take action. Therefore, using "obstacle" captures the essence of what a deterrent does, making it the most suitable choice.

The other options represent concepts that encourage or facilitate action, which are contrary to the intent of a deterrent. For instance, an encourager and an incentive are terms that imply support or motivation to act, while a facilitator refers to someone or something that makes a process easier, all of which do not align with the idea of hindering or preventing actions.