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

Another was an extreme lability of the emotions, so that men with scurvy cried often and unpredictably or succumbed to dangerous fits of temper.

From Slate • Dec. 8, 2016

And this, in turn, may be regarded as but a manifestation of the process of survival by lability rather than by stability.

From Introduction to the Science of Sociology by Park, Robert Ezra