noun

A barrier is something that blocks or obstructs a passage or a way, making it difficult or impossible to pass through. It could be a physical structure like a wall or fence, or a non-physical barrier like a language or cultural difference.

Example

1. The high walls surrounding the castle were an effective barrier against invaders.
2. The language barrier was a major challenge for the international students, making it difficult for them to communicate with their classmates.
3. The lack of access to technology is a significant barrier to education for many children living in rural areas.