Barrier
bar·ri·er
/ˈberēər/
noun
a fence or other obstacle that prevents movement or access.
anything serving to maintain separation by obstructing vision or access
any condition that makes it difficult to make progress or to achieve an objective
A barrier is something such as a rule, law, or policy that makes it difficult or impossible for something to happen or be achieved. Duties and taxes are the most obvious barrier to free trade. Synonyms: obstacle, bar, block, handicap More Synonyms of barrier.
Definitions from Oxford Languages, Collins Dictionary and Vocabulary.com
A barrier is something that blocks the way, such as a fence, railing, or natural obstacle. It can also be something not material that keeps apart or makes progress difficult. For example, criminal background barriers.
Barriers can be physical or metaphorical. They can block movement, barriers can also be a limit or boundary of any kind.