barrier

n. a physical object like a fence or wall that stops people or vehicles from passing.

n. a physical structure or object that prevents movement or separates two areas.

“The police put up a metal barrier to keep the crowd away from the stage.”

“Concrete barriers were installed along the highway to prevent vehicles from crossing into the path of oncoming traffic during the construction phase.”

n. a rule, situation, or problem that prevents someone from doing something or succeeding.

n. an abstract circumstance or obstacle that impedes progress, communication, or social integration.

“The high cost of university can be a major barrier for many students.”

“Language barriers often hinder effective collaboration between international teams, even when all members share a common technical background.”

n. a layer in the body that lets some things in but keeps harmful things out.

n. a physiological structure, such as the blood-brain barrier, that regulates the passage of substances between different compartments of the body.

“The skin acts as a natural barrier against germs and infections.”

“The blood-brain barrier is highly selective, protecting the central nervous system from potentially neurotoxic substances circulating in the blood.”

Technical

v. to close off or block a place using a barrier.

v. to obstruct or enclose a space by means of a physical barrier. Transitive use is less common than the noun form.

“Workers began to barrier the construction site to keep the public safe.”

“The authorities decided to barrier the entrance to the cave after several hikers became lost in the unmapped tunnels.”

Formal