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

A recent Iron Banner overhaul saw the reintroduction of Rift and a new Disjunction map, but neither got PvP players excited.

From The Verge • Sep. 7, 2022

Bungie even appears to have weighted the mode against larger maps like Disjunction, Eternity, and Vostok, so everything feels faster on the smaller maps.

From The Verge • Sep. 7, 2022

Logicians further speak of the Trilemma, with three Hypotheticals and a corresponding triple Disjunction; and of a Polylemma, with any further number of perplexities.

From Logic Deductive and Inductive by Read, Carveth

Disjunction is more frequent in dry fruits than in fleshy ones.

From Vegetable Teratology An Account of the Principal Deviations from the Usual Construction of Plants by Masters, Maxwell T.

Disjunction -- N. disjunction, disconnection, disunity, disunion, disassociation, disengagement; discontinuity &c.

From Roget's Thesaurus of English Words and Phrases by Roget, Peter Mark