Instability

In

• Buckling
• Elastic instability
• Drucker stability of a nonlinear constitutive model
• Biot instability (surface wrinkling in elastomers)
• Baroclinic instability ^[2]

Fluid instabilities

• Ballooning instability (some analogy to the Rayleigh–Taylor instability); found in the magnetosphere
• Atmospheric instability
  • atmospheric dynamics
    )
    • barotropic instability; Helmholtz or shearing instability; rotational instability
  • Hydrostatic instability or static instability/vertical instability (parcel instability), thermodynamic instability (atmospheric thermodynamics)
    • second kind; absolute or mechanical instability
• Bénard instability
• Drift mirror instability
• Kelvin–Helmholtz instability (similar, but different from the diocotron instability in plasmas)
• Rayleigh–Taylor instability
• Plateau-Rayleigh instability
  (similar to the Rayleigh–Taylor instability)
• Richtmyer-Meshkov instability
  (similar to the Rayleigh–Taylor instability)
• Shock Wave Instability
• Benjamin-Feir Instability (also known as modulational instability)

Plasma instabilities

Plasma instabilities can be divided into two general groups (1) hydrodynamic instabilities (2) kinetic instabilities. Plasma instabilities are also categorised into different modes – see this paragraph in plasma stability.

Instabilities of stellar systems

• Bar instability of rapidly rotating disks
• Jeans instability
• Firehose instability^[4]
• Gravothermal instability^[5]
• Radial-orbit instability
• Various instabilities[
  which?
  ] in cold rotating disks

Joint instabilities

The most common residual disability after any sprain in the body is instability. Mechanical instability includes insufficient stabilizing structures and mobility that exceed the physiological limits. Functional instability involves recurrent sprains or a feeling of giving way of the injured joint.