labile

labile \LAY-byl\, adjective:

1. Open to change; apt or likely to change; adaptable.
2. Constantly or readily undergoing chemical, physical, or biological change or breakdown; unstable.

They are too open to the rest of the world, too labile, too prone to foreign influence.
-- Robert Hughes, Goya

Mifflin may not have been much more labile than the people around him, but he was undoubtedly more aware of his volatility.
-- "Leander, Lorenzo, and Castalio", Early American Literature, January 1, 1998

Faber's prose is an amazingly labile instrument, wry and funny, never pretentious, capable of rendering the muck of a London street and the delicate hummingbird flights of thought with equal ease.
-- Lev Grossman, "The Lady Is a Tramp", Time, September 16, 2002

They lock themselves in their studies and from the labile, rocking mass of thoughts and impressions they form books, which immediately become something final, irrevocable, as if frost had cut down the flowers.
-- Adam Zagajewski, "History's children", New Republic, December 2, 1991

Labile derives from Late Latin labilis, from Latin labi, "to slip."