[1] : The Collaborative International Dictionary of English v.0.48

labile \la"bile\, a. l. labilis apt to slip, fr. labi to slip.
   1. liable to slip, err, fall, or apostatize. obs. --cheyne.
      1913 webster

   2. liable or likely to change.
      pjc

   3. chem. easily decomposed or inactivated when subjected to
      heat, radiation, or mildly acidic or alkaline conditions;
      -- of chemical compounds; as, enzymes from thermophilic
      organisms are not as labile as those from mesophiles.
      pjc

[2] : WordNet (r) 2.0

labile
     adj 1: open to change; liable to change; "an emotionally labile
            person"
     2: chemistry, physics, biology readily undergoing change or
        breakdown

Labile >> L Words
Labile, definition of term: Labile
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