disjunction

[dis-juhngk-shuh n] /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 AND or V.
Origin
1350-1400; Middle English disjunccioun < Latin disjunctiōn- (stem of disjunctiō) separation, equivalent to disjunct(us) (see disjunct) + -iōn- -ion
British Dictionary definitions for disjunctions

disjunction

/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 pq 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
Word Origin and History for disjunctions

disjunction

n.

c.1400, disjunccioun, from Old French disjunction (13c.) or directly from Latin disjunctionem "separation," noun of action from past participle stem of disjungere (see disjointed).

disjunctions in Medicine

disjunction dis·junc·tion (dĭs-jŭngk'shən)
n.
The separation of homologous chromosomes during meiosis.