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

He isn’t the first president to face such a disjunction.

From The Wall Street Journal • Dec. 29, 2025

“There’s a pretty sharp disjunction with some sectors bearing the brunt of the cooling we’ve seen in the labor market,” said Guy Berger, principal economist at LinkedIn.

From Washington Post • Jan. 6, 2023

“I’ve never seen a disjunction between the data and the general vibe quite as large as I saw,” said Justin Wolfers, a University of Michigan economist, noting that employment growth is an economic North Star.

From New York Times • Aug. 5, 2022

That disjunction between family lore and Hollywood reality compelled him to write his new book, “Competing With Idiots,” a subjective dual portrait of the Brothers Mankiewicz.

From Los Angeles Times • Sep. 15, 2021

Apart from it being tactically the right thing to do, this disjunction between the man and his job helped Comrade Pillai to keep his conscience clear about his own private business dealings with Chacko.

From "The God of Small Things" by Arundhati Roy