barrier

noun

bar·​ri·​er ˈber-ē-ər 

ˈba-rē-

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

barriers or Barriers plural : a medieval war game in which combatants fight on foot with a fence or railing between them

3

: something immaterial that impedes or separates : obstacle

behavioral barriers

trade barriers

Synonyms of barrier

• wall
• fence
• barricade
• obstacle

Examples of barrier in a Sentence

Concrete barriers surround the race track to protect spectators.

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

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

Both leaders are in favor of removing trade barriers.

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

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

Recent Examples on the Web

The Romeoville barrier does not protect the Des Plaines River above where the river and the Chicago Sanitary and Ship Canal join. — Chicago Tribune, 26 Sep. 2026

Piëch envisioned a car with nearly 1,000 hp that would finally be the first road-going production vehicle to break the 400 kph (249 mph) barrier. — Bradley Iger, Robb Report, 25 Sep. 2026

Robinson, the Dolphins’ 2023 first-round pick, plans to wear a Guardian Cap on his helmet for the foreseeable future, giving himself an extra barrier of protection to prevent continued head trauma. — Omar Kelly, Miami Herald, 24 Sep. 2026

Jaswill Portable Door Lock The pocket-sized device adds an extra barrier to your hotel room door, preventing it from being opened from the outside—even with a key. — Rosie Marder, Travel + Leisure, 24 Sep. 2026

Word History

Etymology

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

First Known Use

14th century, in the meaning defined at sense 1a

Phrases Containing barrier

• barrier island
• barrier reef
• blood-brain barrier
• break the sound barrier
• crash barrier
• Jersey barrier
• language barrier
• sonic barrier
• sound barrier
• the sound barrier
• vapor barrier

Rhymes for barrier

• carrier
• noncarrier

Kids Definition

barrier

noun

bar·​ri·​er ˈbar-ē-ər 

1

: something (as a fence, railing, or natural obstacle) that blocks the way

2

: something not material that keeps apart or makes progress difficult

language barriers

Medical Definition

barrier

noun

bar·​ri·​er ˈbar-ē-ər 

1

a

: a material object or set of objects that separates, demarcates, or serves as a barricade see blood-brain barrier, placental barrier

b

: 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

: a factor that tends to restrict the free movement, mingling, or interbreeding of individuals or populations

behavioral and geographic barriers to hybridization