lability

American  

[luh-bil-i-tee, ley-] / ləˈbɪl ɪ ti, leɪ- /

noun

1. the fact or quality of being likely to change.

   The lability of the neuromuscular system during physical therapy was measured in muscle force and reaction times.

2. Chemistry, Biochemistry. the ability or likelihood of a substance or compound to change or break down easily, rapidly, or continually.

   It was found that the degree of lability varies considerably with different amido-aldehydes.

3. Psychiatry. the unregulated or unstable state of emotions or mood, characterized by exaggerated affective expression.

   They were concerned about his emotional lability, from flaring anger one moment to maudlin sentimentality the next.

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Etymology

Origin of lability

First recorded in 1550–60 in a different sense; equivalent to Latin lābili(s) “sliding, slipping” ( see labile ( def. )) + -tās -ty ² ( def. )

Example Sentences

Emotional lability is a common symptom of prion disease.

From Science Magazine • Mar. 21, 2024

In his book “Why We Sleep,” the neuroscientist Matthew Walker half-jokes that dreams are a time when everyone on Earth becomes “flagrantly psychotic,” experiencing hallucinations, delusions, disorientation, emotional lability and amnesia.

From New York Times • Nov. 3, 2021

The boredom, frustration, mortification, warmth, impulsiveness, lability, silliness, bewilderment and capacity to forgive.

From Washington Post • Mar. 27, 2021

The show, if we are interested in judging success, succeeds in failing to contain camp’s affective lability.

From Slate • May 14, 2019

Their life seems to be one long series of impulsions, fostered and sustained by the extreme lability of their emotions.

From Studies in Forensic Psychiatry by Glueck, Bernard