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noun bar·ri·er \ˈber-ē-ər, ˈba-rē-\

Simple Definition of barrier

  • : something (such as a fence or natural obstacle) that prevents or blocks movement from one place to another

  • : a law, rule, problem, etc., that makes something difficult or impossible

  • : something that makes it difficult for people to understand each other

Source: Merriam-Webster's Learner's Dictionary

Full Definition of barrier

  1. 1 a :  something material that blocks or is intended to block passage <highway barriers> <a barrier contraceptive> b :  a natural formation or structure that prevents or hinders movement or action <geographic barriers to species dissemination> <barrier beaches> <drugs that cross the placental barrier>

  2. 2 plural often capitalized :  a medieval war game in which combatants fight on foot with a fence or railing between them

  3. 3 :  something immaterial that impedes or separates :  obstacle <behavioral barriers> <trade barriers>

Examples of barrier in a sentence

  1. Concrete barriers surround the race track to protect spectators.

  2. The tree's roots serve as a barrier against soil erosion.

  3. The mountain range forms a natural barrier between the two countries.

  4. Both leaders are in favor of removing trade barriers.

  5. Cultural barriers have made it hard for women to enter many professions.

  6. He argues that regulations should not be viewed as barriers to progress.

Origin and Etymology of barrier

Middle English barrere, from Anglo-French, from barre bar

First Known Use: 14th century

BARRIER Defined for Kids


noun bar·ri·er \ˈber-ē-ər\

Definition of barrier for Students

  1. 1 :  something (as a fence) that blocks the way

  2. 2 :  something that keeps apart or makes progress difficult <a language barrier>

Medical Dictionary


noun bar·ri·er \ˈbar-ē-ər\

Medical Definition of barrier

  1. 1a:  a material object or set of objects that separates, demarcates, or serves as a barricade—see blood-brain barrier, placental barrierb:  a contraceptive device (such as a condom or cervical cap) that prevents sperm from entering the uterus—often used before another noun <barrier contraception>

  2. 2:  a factor that tends to restrict the free movement, mingling, or interbreeding of individuals or populations <behavioral and geographic barriers to hybridization>

Seen and Heard

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a sculptured or ornamented band

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