Definition of "unstable" []

• Tending strongly to change: unstable weather. (adjective)
• Not constant; fluctuating: unstable vital signs. (adjective)
• Fickle. (adjective)
• Lacking control of one's emotions; marked by unpredictable behavior. (adjective)
• Not firmly placed; unsteady: an unstable ladder. (adjective)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "On the other hand, the term unstable does not necessarily mean that there are problems - rather, that enhancements or changes have been made to the software that have not undergone rigorous testing and that more changes are expected to be imminent."
• "Police also seized what they called unstable explosives stored in a heavily populated area of Copenhagen."
• "Keeping the rest of the world unstable is the name of the game."