from The American Heritage® Dictionary of the English Language, 5th Edition.

  • adjective Tending strongly to change.
  • adjective Not constant; fluctuating.
  • adjective Wavering or fickle.
  • adjective Showing or marked by erratic or volatile emotions or behavior.
  • adjective Not firmly placed; unsteady.
  • adjective Decomposing readily.
  • adjective Highly or violently reactive.
  • adjective Decaying with relatively short lifetime. Used of subatomic particles.
  • adjective Radioactive.

from The Century Dictionary.

  • To make no longer a stable or filthy abode.
  • Not stable; not fixed.
  • Not steady; inconstant; irresolute; wavering.

from the GNU version of the Collaborative International Dictionary of English.

  • adjective Not stable; not firm, fixed, or constant; subject to change or overthrow.
  • adjective See Stable equilibrium, under Stable.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

  • adjective having a strong tendency to change
  • adjective fluctuating; not constant
  • adjective fickle
  • adjective unpredictable
  • adjective chemistry Readily decompasable
  • adjective physics Radioactive, especially with a short half-life

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • adjective subject to change; variable
  • adjective disposed to psychological variability
  • adjective highly or violently reactive
  • adjective lacking stability or fixity or firmness
  • adjective affording no ease or reassurance
  • adjective suffering from severe mental illness


from Wiktionary, Creative Commons Attribution/Share-Alike License

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