unstable Definition
un·sta·ble (-stā′bəl)
adjective
not stable; specif.,
- not fixed, firm, or steady; easily upset or unbalanced
- changeable; variable; fluctuating
- unreliable; fickle
- emotionally unsettled
- Chem. tending to decompose or change into other compounds
Etymology: ME
- unstack
- unstained
- unstalked
- unstamped
- unstandardized
- unstarched
- unstarred
- unstated
- unstatesmanlike
unstable Related Forms
unstable Synonyms
unstable
modif.
Having a high center of gravity
unsteady, wavering, unbalanced, giddy, wobbly, wiggly, weaving, shifty, precarious, top-heavy, teetering, shifting, uncertain, rattletrap, beetling, jutting, lightly balanced. Easily disturbed
variable, changeable, inconstant, giddy, capricious, fluctuating, shifty, volatile, rootless, dizzy, unpredictable, uncertain, sensitive, oversensitive, thin-skinned, timid, delicate. Subject to fission
fissionable, fissiparous, fractionable; see weak 2. See syn. study at inconstant.
unstable Usage Examples
Preposition: at
speed: Ryan Farquhar on the MSS Discovery Kawasaki was the early leader, but retired as the bike was proving unstable at high speeds.
Adjective complement with noun phrase
make: Even when the injury has healed, scar tissue can cause epilepsy by making electrical activity unstable in that area of the brain.
Modifies a noun
- angina: People with frequent angina pains or unstable angina should avoid flying.
- manifold: The most frequently used example is the unstable manifold of a periodic orbit that just lost its stability in a period-doubling bifurcation.
- equilibrium: The origin is an unstable equilibrium corresponding to the vertical position above the pivot.
- orbit: Such unstable orbits can be stabilized by tiny control forces.
- boulder: Description: Boulders were removed from the entrance to facilitate entry to a 2m free climb down past unstable boulder to a tight rift.
- nucleus: H Be able to attribute this decrease in activity to a corresponding decrease in the number of unstable nuclei.
Modifying Another Word
- inherently: Access via the Internet The internet is an inherently unstable medium.
- mentally: Let's hope the sudden absence of Big Brother doesn't tip our mentally unstable friends over the edge.
- structurally: Artificial constructs are well-known to be structurally unstable ( 7 ).
- haemodynamically: It covers paroxysmal, persistent and permanent AF, considers AF developing after surgical procedures, and offers advice on haemodynamically unstable AF.
- dangerously: The area below the Great Aven in Simpsons Pot, Kingsdale is dangerously unstable.
- emotionally: This aspect can cause you to be somewhat emotionally unstable.
Used with adjective complement
- become: My gait became unstable; my arms became weak; I dropped things; doing my hair became a chore.
- appear: The possible route onwards appears unstable with boulders in clay.
- remain: The patient's condition remained unstable requiring further blood replacement.
- prove: Ryan Farquhar on the MSS Discovery Kawasaki was the early leader, but retired as the bike was proving unstable at high speeds.
- seem: Dave Yates Should be a great box but seems slightly unstable.
- feel: The criteria for discharge are that the patient should be able to walk unaided without stumbling or feeling unstable.
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