That which deters or prevents.

something immaterial that interferes with or delays action or progress

an attempt to prevent or discourage an action before it is initiated generally through fear or doubt

an attempt to prevent or discourage an action before it is taken, thus mitigating a threat

Something meant to frighten people, in order to prevent them from committing a crime.

Any physical or psychological device or method that discourages action. In the physical security arena, locks or window grills are physical deterrents and the presence of a guard or surveillance camera are psychological deterrents.

Something that prevents or restrain by fear

Substance used to prevent a cat from accessing a particular area