Definition of labile in US English:



  • 1Liable to change; easily altered.

    unpredictable, inconsistent, changeable, variable, inconstant, uncertain, irregular, unstable, turbulent, unsteady, unsettled, unreliable, undependable, changing, ever-changing, volatile, varying, shifting, fluctuating, fluid, mutable, protean, fitful, wavering, full of ups and downs
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    1. 1.1 Of or characterized by emotions that are easily aroused or freely expressed, and that tend to alter quickly and spontaneously; emotionally unstable.
      • ‘An illustrative case is a 29-year-old clerical worker in England noted to be depressed, emotionally labile and socially withdrawn.’
      • ‘She may be labile and inconsistent, expressing strong emotions of various types without any solid reason.’
      • ‘Objectively, he is emotionally labile and becomes jittery and nervous when discussing the ring.’
      • ‘He experienced labile mood, irritability, and ‘a racing heart’.’
      • ‘Only emotionally labile noncompliance was a significant predictor of peer rejection.’
      evaporative, vaporous, vaporescent
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    2. 1.2Chemistry Easily broken down or displaced.
      • ‘A new class of thermally labile compounds having rust inhibiting properties is disclosed and claimed.’
      • ‘This is consistent with perceptions that lipids are more labile than nonlipids.’
      • ‘However, water stress interacting with CO2 enhanced the shift of the carbon from the labile pool to recalcitrant pool.’
      • ‘The chemical exchange of labile deuterons was measured as described previously, using an inversion-transfer technique.’
      • ‘We know that elements are labile things, which is why lead water pipes and lead-based paints are no longer manufactured, and why aluminium cooking utensils are (rightly or wrongly) accused on suspicion of causing dementia.’


Late Middle English (in the sense ‘liable to err or sin’): from late Latin labilis, from labi ‘to fall’.