Word.ws English Dictionary

regular open

regular open adjective: being the interior of its closure.

Adjective

regular open (not comparable)

  1. (rare) Being the interior of its closure.
    • The set (0,1)∪(1,2) is open, but is not regular open, because its closure is [0,2], so the interior of its closure is (0,2).

Origin of regular open

From regular + open; apparently a backformation from regular open set.

Questions about regular open

What does regular open mean?
Regular open means being the interior of its closure.
What part of speech is regular open?
Regular open is an adjective.

Words near regular open in the dictionary

  1. regular map
  2. regular maps
  3. regular muscle prism
  4. regular muscle-prism
  5. regular necrophiliac
  6. regular open
  7. regular order
  8. regular polygon
  9. regular polygons
  10. regular polyhedra
  11. regular polyhedron

Source and license

Adapted from Wiktionary: regular open (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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Cite this entry: “regular open.” Word.ws, https://word.ws/regular_open. Based on Wiktionary, CC BY-SA 4.0.