# barrier

Pronunciation: US say "BA-ree-ur" /ˈbæɹi.ɚ/; UK say "BA-ree-uh" /ˈbæɹi.ə(ɹ)/

## Noun

1. A structure built to block the way and prevent passage from one side to the other.
   - Simple: Something solid put in place to stop people or things from getting through.
   - _Police set up a barrier across the road to redirect traffic._
   - _Concrete barriers lined both sides of the highway._
2. An obstacle or impediment that stands in the way of progress or makes something difficult to achieve.
   - Simple: Something that makes it hard or impossible to do something or move ahead.
   - _Language can be a serious barrier when you move to a new country._
   - _The company worked to remove the barriers facing disabled employees._
3. A boundary or limit that separates one thing from another or marks how far something can extend.
   - Simple: A point or edge that marks how far something can go.
   - _The plane finally broke the sound barrier over the desert._
   - _Scientists pushed past the barrier of what was once thought possible._
5. A separation between two areas of the body where specialized cells admit certain substances while preventing the entry of others.
   - Simple: A wall of special cells in the body that lets some things through but keeps others out.
   - _The barrier surrounding the brain admits oxygen and glucose while excluding many toxins._
   - _Specialized cells form a barrier that selectively controls what enters the tissue._
6. In government and binding theory, a node that intervenes between two others when it can potentially govern the lower node, c-commands it, and does not c-command the higher one.
   - Simple: In a theory of grammar, a part of a sentence's structure that stands between two others and stops them from connecting.
   - _Whether a phrase counts as a barrier determines if government can reach the lower node._
   - _The analysis hinges on identifying which maximal projection acts as a barrier._
7. The enclosed ground within which combatants fought at a medieval tournament.
   - Simple: The fenced area where knights fought each other in old tournaments.
   - _The herald announced each knight as he entered the barrier._
   - _Spectators crowded the rails around the barrier to watch the joust._
8. A martial exercise of the fifteenth and sixteenth centuries, in which combatants fought on foot across a low rail.
   - Simple: A kind of fighting contest from long ago, fought across a low rail.
   - _The court held a barrier in honor of the visiting prince._
   - _Knights tested their skill at the barrier before the evening feast._

## Verb

4. To block or obstruct a route or opening by placing a structure across it.
   - Simple: To block a way or path with something that stops people or things passing.
   - _Officials barrier the bridge whenever flooding threatens the town._
   - _Volunteers barriered the road to protect the marathon runners._

## Origin

From Middle English barryer, from Old French barriere (compare modern French barrière), which came from Old French barre meaning "bar."

Source: DictionaryAI, https://dictionaryai.com/define/barrier (written from Wiktionary data, CC BY-SA 4.0: https://creativecommons.org/licenses/by-sa/4.0/).