dissociation

American  

[dih-soh-see-ey-shuhn, -shee-ey-] / dɪˌsoʊ siˈeɪ ʃən, -ʃiˈeɪ- /

noun

1. an act or instance of dissociating.

2. the state of being dissociated; disjunction; separation.

   the dissociation of church and state.

3. Physical Chemistry.

   1. the reversible resolution or decomposition of a complex substance into simpler constituents caused by variation in physical conditions, as when water gradually decomposes into hydrogen and oxygen under great heat in such a way that when the temperature is lowered the liberated elements recombine.

   2. electrolytic dissociation.

4. Psychiatry. the splitting off of a group of mental processes from the main body of consciousness, as in amnesia or certain forms of hysteria.

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dissociation British  

/ dɪˌsəʊsɪˈeɪʃən, -ʃɪ- /

noun

1. the act of dissociating or the state of being dissociated

2. chem

   1. a reversible chemical change of the molecules of a single compound into two or more other molecules, atoms, ions, or radicals

   2. any decomposition of the molecules of a single compound into two or more other compounds, atoms, ions, or radicals

3. separation of molecules or atoms that occurs when a liquid or solid changes to a gas

4. psychiatry the separation of a group of mental processes or ideas from the rest of the personality, so that they lead an independent existence, as in cases of multiple personality

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dissociation Scientific  

/ dĭ-sō′sē-ā′shən /

1. The separation of a substance into two or more simpler substances, or of a molecule into atoms or ions, by the action of heat or a chemical process. Dissociation is usually reversible.

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Other Word Forms

• self-dissociation
  noun

Etymology

Origin of dissociation

First recorded in 1605–15; dis- ¹ + (as)sociation, modeled on Latin dissociātiō “separation”

Example Sentences

After she disappears yet again, Aviv accompanies Upp’s mother, herself no stranger to dissociation, as she vainly tracks her missing daughter — and connects instead with other lost women.

From Los Angeles Times • Jul. 8, 2026

This stabilized the ions, lowered the energy required for water to split, and increased the amount of dissociation.

From Science Daily • Jul. 2, 2026

Anna's daughter has a number of diagnoses including pre-verbal trauma and a dissociation disorder, which manifests as multiple personalities.

From BBC • Feb. 17, 2026

He added, “I have suffered from dissociation all my life, but somehow the linkage between ‘qi’ and art has given me focus and hope.”

From New York Times • May 2, 2024

There was a dissociation of form and substance.

From "The Great Santini" by Pat Conroy