[1] : The Collaborative International Dictionary of English v.0.48

instability \in`stabil"ity\, n.; pl. instabilities. l.
   instabilitas: cf. f. instabilit'e.
   1913 webster
   1. the quality or condition of being unstable; lack of
      stability, firmness, or steadiness; liability to give way
      or to fail; insecurity; precariousness; as, the
      instability of a building.
      1913 webster

   2. lack of determination of fixedness; inconstancy;
      fickleness; mutability; changeableness; as, instability of
      character, temper, custom, etc. --addison.

   syn: inconstancy; fickleness; changeableness; wavering;
        unsteadiness; unstableness.
        1913 webster
see also:
instabilities 

[2] : WordNet (r) 2.0

instability
     n 1: an unstable order ant: stability
     2: unreliability attributable to being unstable
     3: a state of disequilibrium as may occur in cases of inner
        ear disease syn: imbalance, unbalance ant: balance
     4: the quality or attribute of being unstable and irresolute
        syn: unstableness ant: stability, stability
see also:
stability imbalance unbalance balance unstableness 

[3] : Moby Thesaurus II by Grady Ward, 1.0

146 moby thesaurus words for "instability":
   ambitendency, ambivalence, caducity, capriciousness, chanciness,
   change of mind, changeability, changeableness, choppiness,
   corruptibility, criticalness, danger, dappleness, death,
   decrepitude, delicacy, desultoriness, deviability, deviation,
   difference, differentiation, disorder, divarication, divergence,
   diversification, double-mindedness, doubtfulness, dubiety,
   dubiousness, eccentricity, ephemerality, ephemeralness, erraticism,
   evanescence, fence-sitting, fence-straddling, fickleness, finitude,
   fleetingness, flightiness, freakishness, fugacity, hazard,
   hazardousness, impermanence, impermanency, impulsiveness,
   incapacity, inconsistency, inconstancy, indecision, indecisiveness,
   inequality, infirmity, infirmity of purpose, insecurity,
   insipidity, insolidity, insubstantiality, invalidism, irregularity,
   irresolution, jerkiness, mercuriality, momentariness, moodiness,
   mortality, motleyness, mugwumpery, mugwumpism, mutability,
   nonconformism, nonconformity, nonstandardization, nonuniformity,
   peril, perilousness, perishability, pluralism, precariousness,
   raggedness, restlessness, ricketiness, risk, riskiness,
   second thoughts, senility, shakiness, shiftiness, shiftingness,
   slipperiness, speculativeness, sword of damocles, tergiversation,
   ticklish business, ticklishness, totteriness, touchiness,
   transience, transiency, transientness, transitoriness,
   treacherousness, treachery, unauthenticity, unauthoritativeness,
   uncertainty, unconformism, unconformity, undecidedness,
   undependability, undeterminedness, unevenness, unfaithworthiness,
   unfirmness, unfixedness, unhealthiness, unorthodoxy,
   unpredictability, unreliability, unsafeness, unsettledness,
   unsettlement, unsolidity, unsoundness, unstableness,
   unsteadfastness, unsteadiness, unsturdiness, unsubstantiality,
   unsureness, untrustworthiness, vapidity, variability, variation,
   variegation, variety, variousness, versatility, volatility,
   wantonness, wateriness, wavering, waywardness, whimsicality,
   wishy-washiness

Instability >> I Words
Instability, definition of term: Instability
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