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Medical Dictionary

barrier

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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>





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