a. 不安定的, 易发生变化的

[医] 不稳定的, 易变的

Labile \La"bile\, a. [L. labilis apt to slip, fr. labi to slip.]
1. Liable to slip, err, fall, or apostatize. [Obs.] --Cheyne.

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]