disjunction

American  

[dis-juhngk-shuhn] / dɪsˈdʒʌŋk ʃən /

noun

1. the act of disjoining or the state of being disjoined.

   a disjunction between thought and action.

2. Logic.

   1. Also called disjunctive, inclusive disjunction.  a compound proposition that is true if and only if at least one of a number of alternatives is true.

   2. Also called exclusive disjunction.  a compound proposition that is true if and only if one and only one of a number of alternatives is true.

   3. the relation among the components of such a proposition, usually expressed by OR or V.

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disjunction British  

/ dɪsˈdʒʌŋkʃən /

noun

1. Also called: disjuncture.  the act of disconnecting or the state of being disconnected; separation

2. cytology the separation of the chromosomes of each homologous pair during the anaphase of meiosis

3. logic

   1. the operator that forms a compound sentence from two given sentences and corresponds to the English or

   2. a sentence so formed. Usually written p ∨ q where p, q are the component sentences, it is true (inclusive sense) whenever either or both of the latter are true; the exclusive disjunction, for which there is no symbol, is true when either but not both disjuncts is

   3. the relation between such sentences

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Etymology

Origin of disjunction

First recorded in 1350–1400; Middle English disjunccioun from Latin disjunctiōn- (stem of disjunctiō ) “separation,” equivalent to disjunct(us) ( see disjunct ( def. )) + -iōn- -ion ( def. )

Explanation

A disjunction is a broken connection. If you expect to be a doctor but you haven't taken any science courses since high school biology, you would have a disjunction between your expectations and your training. The -junct- in disjunction is the same Latin root that gives us yoke, the harness that joins two oxen together. So if you have a disjunction, things are not joined together — there's a disconnect. If you order a pizza and the waiter brings you caviar, that's a disjunction. In logic, a disjunction is made by joining two sentences with "or" — "I'm tired, or I'm hungry" — while a conjunction joins two sentences with "and" — "I'm tired, and I'm hungry."

Example Sentences

There is a disjunction at the heart of children’s literature.

From The Wall Street Journal • Dec. 12, 2025

It’s tempting to point out the disjunction between the author’s fundamental outsider stance and his postmortem embrace by the institutional intelligentsia.

From Washington Post • Apr. 13, 2023

Guest curator Alissa Anderson Campbell identifies the artist’s radical political views, but their disjunction with his commitment to traditional, even conservative painting styles remains a conundrum.

From Los Angeles Times • Sep. 6, 2022

Through the disjunction between the narration and the street scenes, Akerman in effect divides viewers’ attentions the way hers were presumably divided.

From New York Times • Aug. 26, 2022

The disjunction between the prince’s all-too-human genetic inheritance and his all-too-exalted political inheritance must have seemed particularly evident to the critics of the monarchy.

From "The Gene" by Siddhartha Mukherjee