Word.ws English Dictionary

porous portals

porous portals is the plural of porous portal.

Meaning of porous portal

Noun

porous portal (plural porous portals)

  1. A type of extended and perforated tunnel portal on high-speed railways, designed to reduce the build-up of pressure when a train enters a tunnel at high speed.
    • The Down line portal will measure 220 metres in length, while the Up line portal will be 135 metres long. Known as 'porous portals', they will (as the name suggests) be punctuated with holes. These holes or vents slow the build-up of pressure created by trains within the tunnels. The resulting...2024 March 20, Chris Howe, “High speed underneath the Chilterns...”, in RAIL, number 1005, page 33

Questions about porous portals

What is porous portals the plural of?
Porous portals is the plural of porous portal.

Words near porous portals in the dictionary

  1. porottas
  2. porotype
  3. porotypes
  4. porous
  5. porous portal
  6. porous portals
  7. porously
  8. porousness
  9. porousnesses
  10. poroviscoelastic
  11. poroviscoelasticity

Source and license

Adapted from Wiktionary: porous portals (page history and authors); porous portal (page history and authors). Text available under the Creative Commons Attribution-ShareAlike 4.0 license. Word.ws reformatted the entry and added links. Wiktionary data of 2026-09-02.

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