adjective Liable to slip, err, fall, or apostatize.
adjective Apt or likely to change.
adjective Of a compound or bond, kinetically unstable; rapidly cleaved (and possibly reformed).
Certain drugs can be conjugated to polymer molecules with a linkage that is labile at low pH to effect controlled release in a cellular endosome.
adjective Of a verb, able to change valency without changing its form; especially, able to be used both transitively and intransitively without changing its form.