Word.ws English Dictionary

disjoint union

disjoint union noun: a union of sets forced to be disjoint by attaching information referring to the original sets to their elements (i.e., by using indexing).

Noun

disjoint union (plural disjoint unions)

  1. A union of sets forced to be disjoint by attaching information referring to the original sets to their elements (i.e., by using indexing).
    Synonyms:
    discriminated union
  2. A union of sets which are already pairwise disjoint.
    Synonyms:
    discriminated union
  3. The disjoint union of the underlying sets of a given family of topological spaces, equipped with a topology.
    Synonyms:
    coproduct, direct sum, free sum, free union, topological sum

Synonyms of disjoint union

Forms of disjoint union

pluraldisjoint unions

Words formed from disjoint union

Questions about disjoint union

What does disjoint union mean?
Disjoint union means a union of sets forced to be disjoint by attaching information referring to the original sets to their elements (i.e., by using indexing).
What part of speech is disjoint union?
Disjoint union is a noun.
What is the plural of disjoint union?
The plural of disjoint union is disjoint unions.

Words near disjoint union in the dictionary

  1. disjoining
  2. disjoins
  3. disjoint
  4. disjoint set
  5. disjoint sets
  6. disjoint union
  7. disjoint union topologies
  8. disjoint union topology
  9. disjoint unions
  10. disjointed
  11. disjointedly

Source and license

Adapted from Wiktionary: disjoint union (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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