: readily or continually undergoing chemical, physical, or biological change or breakdown : unstable
a labile mineral
: readily open to change
has so labile a face that some of her scenes … rock with emotionManny Farber
lability noun

Did you know?

Labile was borrowed into English from French and can be traced back (by way of Middle French labile, meaning "prone to err") to the Latin verb labi, meaning "to slip or fall." Indeed, the first sense of labile in English was "prone to slip, err, or lapse," but that usage is now obsolete. Other labi descendants in English include collapse, elapse, and prolapse, as well as lapse itself.

Examples of labile in a Sentence

Recent Examples on the Web There was something kinetic, something labile in his air. Kevin Barry, The New Yorker, 8 Apr. 2024 Amid this high level of acting skill, Lindsey stood out with her wonderfully convincing gestures and facial expressions, filling out the character of the more labile younger sister with captivating verisimilitude. Jeremy Yudkin, BostonGlobe.com, 17 July 2023 To be labile is to be unstable; in chemistry, a labile substance is easily broken down. Maureen Stanton, Longreads, 10 Aug. 2020 On unusually chilly days, these climatically labile folks are 0 for 3. Valerie Ross, Discover Magazine, 8 Apr. 2011 The painting, which ostensibly depicts Mary Magdalene in the reveries of devotion, is less spiritual than erotic: her interlaced fingers may be motionless, but her slight smile seems labile, indicating that Artemisia understood a woman’s sensuality from the inside out. Rebecca Mead, The New Yorker, 28 Sep. 2020 According to the consolidation/reconsolidation hypothesis, recently acquired or reactivated memories are transformed progressively from an initially labile state into a stable form, through a protein-dependent process. Neuroskeptic, Discover Magazine, 22 Sep. 2015 Moreover, climate can be quite labile, with natural variation causing lots of ups and downs. Tom Yulsman, Discover Magazine, 12 Mar. 2016 In its particulars, that work prefigured much that was to come: public, politically labile, made with sparse means and leaving no object behind. New York Times, 4 Dec. 2021

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'labile.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


French, from Middle French, prone to err, from Late Latin labilis, from Latin labi to slip — more at sleep

First Known Use

1603, in the meaning defined at sense 1

Time Traveler
The first known use of labile was in 1603


Dictionary Entries Near labile

Cite this Entry

“Labile.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/labile. Accessed 29 May. 2024.

Medical Definition


la·​bile ˈlā-ˌbīl How to pronounce labile (audio) -bəl How to pronounce labile (audio)
: readily or frequently changing: as
: readily or continually undergoing chemical, physical, or biological change or breakdown
a labile antigen
: characterized by wide fluctuations (as in blood pressure or glucose tolerance)
labile hypertension
labile diabetes
: emotionally unstable
lability noun
plural labilities
Last Updated: - Updated example sentences
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