Skip to main content
unstable

unstable

80 4.4
Not steady and likely to change, fail, or fall
  • adjective
  • /ʌnˈsteɪbəl/
translation icon : inestable
  • The sculpture at the gallery was unstable and needed support to prevent it from falling.
  • politically unstable
  • stable or unstable
  • an unstable environment

And that's a very, a, a very unstable set up, as it turns out.

Autoplay Next

Examples

  • The bridge was deemed unsafe because it had become unstable after the earthquake.

  • A massive up day is just as unstable as a massive down day.

  • Information and intelligence were unstable and hard to judge.

  • Long hours, unstable income, back breaking work.

  • But obviously social media can be a very unstable job.

  • This is an unstable system, and this town should be on alert.

  • Her coordination is unstable at best.

  • At the same time, the image of Pocahontas in the American mind has been an unstable one.

    Academic text (2015)
  • Suspension of debt service resulted in an unstable investment climate and a decline in capital inflows.

    Academic text (1990)
  • So I came twirling towards the ground with an unstable parachute above my head.

Synonyms

unpredictable
vsunstable
163 4.4

Likely to change suddenly and hard to know in advance

is less about surprise and more about not being steady or secure
erratic
vsunstable
94 6.1

Not regular or predictable and likely to change suddenly

is broader, also covering physical or lasting lack of steadiness
volatile
vsunstable
77 7.0

Likely to change suddenly and become more dangerous

is similar but may also mean simple lack of lasting firmness
shaky
vsunstable
53 3.3

Not firm or safe and likely to fail

is more general, covering both physical and lasting insecurity
precarious
vsunstable
47 7.6

In a dangerous, unstable position likely to fall or fail

is often less about danger and more about general insecurity
fluid
vsunstable
43 5.1

Not fixed or stable and likely to change

can imply unwanted change or failure rather than flexible change
fickle
vsunstable
39 6.2

Changing often in a way you cannot rely on

is wider, applying to general lack of stability beyond feelings
wobbly
vsunstable
36 3.6

Unsteady and likely to move from side to side

is broader, applying also to nonphysical lack of steadiness
turbulent
vsunstable
34 6.6

Full of confusion and disorder among people, politics, or events

is broader, including milder forms of not being steady or secure
unsteady
vsunstable
16 3.3

Not firm or balanced and likely to fall

is broader, meaning not steady, secure, or likely to last
unreliable
vsunstable
10 4.3

Not safe because it might fail or break

is broader, meaning not steady or likely to last in general
flaky
vsunstable
  • Informal
6 7.0

Tending to fail or change without warning

is the general state of not being steady or secure
inconstant
vsunstable
2 7.5

Changing often and not staying the same

includes that but also covers physical unsteadiness and failure risk
unsettled
vsunstable
2 4.3

Weather that often changes, bringing rain or strong wind

applies to those cases and to general lack of lasting security
labile
vsunstable
1 9.7

Able to change or break down easily

is the general condition of not being steady or secure
unfirm
vsunstable
1 8.0

Soft ground that moves or sinks easily

extends that idea to lasting insecurity or tendency to change
unsturdy
vsunstable
4.8

Likely to wobble or break, like a weak chair

covers both weak build and broader chances of change or failure
unsecure
vsunstable
4.4

Not firmly fixed and likely to come loose

also includes instability that causes change, not only fastenings
toty
vsunstable
  • UK
9.9

Shaky and likely to fall over when you touch it

can mean that or a general lack of lasting security
tottering
vsunstable
7.5

Unstable and likely to fall or fail soon

is less extreme, including milder chances of change or failure
fluctuating
vsunstable
6.1

Changing up and down often in a way you cannot guess

is more general, covering lasting insecurity or failure risk

Antonyms

473 2.3

Not likely to change and stays steady over time

How Stable

secure
86 3.3
stable
473 2.3
unsteady
16 3.3
unstable
80 4.4
precarious
47 7.6

Surface Forms

unstable positive
unstabler comparative
unstablest superlative

Morphology

unstable = stable (transparent) = un + stable

The meaning is a straightforward negation formed by productive English prefix 'un-' applied to 'stable', yielding 'not stable'.

Etymology

Unstable is built from un- meaning 'not' and stable meaning 'standing firm' or 'steady'. So when something is unstable it does not 'stand firm' and can change, fall, or fail.