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adj. un·sta·bler, un·sta·blest
a. Tending strongly to change: unstable weather.
b. Not constant; fluctuating: unstable vital signs.
a. Wavering or fickle: At first, he was unstable in his decisions.
b. Showing or marked by erratic or volatile emotions or behavior.
3. Not firmly placed; unsteady: an unstable ladder.
4. Chemistry
a. Decomposing readily.
b. Highly or violently reactive.
5. Physics
a. Decaying with relatively short lifetime. Used of subatomic particles.
b. Radioactive.

un·sta′ble·ness n.
un·sta′bly adv.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.unstableness - the quality or attribute of being unstable and irresoluteunstableness - the quality or attribute of being unstable and irresolute
unsteadiness - the quality of being unsteady--varying and unpredictable
shakiness - the quality of being unstable and insecure; "the shakiness of the present regime"
stability, stableness - the quality or attribute of being firm and steadfast


1. The quality or condition of being physically unsteady:
2. The quality or condition of being erratic and undependable:
References in periodicals archive ?
Because calculation for moving vehicle takes extra time to re-mesh around the vehicle, and also needs smaller time step due to the unstableness of the calculation.
Because of a perceived inherent unstableness and irrationality, such crowds were seen to need disciplining, to have their energies usefully and responsibly channeled.
This reveals both the unstableness of personalist autocracies and the way violence is constantly employed as a last resort to resolve intra-elite conflicts in authoritarian environments.
The reason why we do not compare our algorithm with other conventional methods such as motion analysis based or shot boundary based methods is that they are inefficient for video indexing and not easily applicable to compressed domain scheme due to many computations and unstableness.