English Wikipedia has an article on:

barrier

Wikipedia

From Middle English barryer, barrere, barryȝer, from Old French barriere (compare French barrière), from Old French barre (“bar”).

• (UK) IPA^(key): /ˈbæɹi.ə(ɹ)/
• (US, without the Mary–marry–merry merger) IPA^(key): /ˈbæɹi.ɚ/
• (US, Mary–marry–merry merger) IPA^(key): /ˈbɛɹi.ɚ/

• Audio (US):

  (file)

• Rhymes: -æɹiə(ɹ)

barrier (plural barriers)

1. A structure that bars passage.

   The bus went through a railway barrier and was hit by a train.

   The bomber had passed through one checkpoint before blowing himself up at a second barrier.

2. An obstacle or impediment.

   Even a small fee can be a barrier for some students.

   • 2013 June 1, “Towards the end of poverty”, in The Economist‎^[1], volume 407, number 8838, page 11:

     America’s poverty line is $63 a day for a family of four. In the richer parts of the emerging world $4 a day is the poverty barrier. But poverty’s scourge is fiercest below $1.25 ([…]): people below that level live lives that are poor, nasty, brutish and short.

3. A boundary or limit.

   Few marathon runners break the three-hour time barrier.

   • 2025 April 21, Charles Hugh Smith, What's "Normal" in a Hyper-Normalized World?‎^[2]:

     The downside of normalization is that it erects a defensive barrier between the real world and the perceived i.e. normalized world.

4. (grammar) A node (in government and binding theory) said to intervene between other nodes A and B if it is a potential governor for B, c-commands B, and does not c-command A.
5. (physiology) A separation between two areas of the body where specialized cells allow the entry of certain substances but prevent the entry of others.
6. (historical) The lists in a tournament.
7. (historical, in the plural) A martial exercise of the 15th and 16th centuries.

• See also Thesaurus:hindrance

barrier (third-person singular simple present barriers, present participle barriering, simple past and past participle barriered)

1. (transitive) To block or obstruct with a barrier.

   Synonym: bar