unstable
gb/ʌnstˈeɪbəl/ us/ʌnstˈeɪbəl/
B1
English
~ 7500
instabil, ingatag, bizonytalan, változékony, labilis, mentálisan instabil, érzelmileg labilis, bomlékony
B1
1
Usage pattern:
[something] is unstable / an unstable [object/structure]
The old wooden bridge felt unstable under our feet.
A régi fahíd ingatagnak tűnt a lábunk alatt.
Put the baby gate back on; it’s unstable if you don’t lock it properly.
Tedd vissza a babakaput; instabil, ha nem rögzíted rendesen.
After the earthquake, several buildings were declared structurally unstable.
The stack of boxes is too high and looks very unstable.
He fell because the chair was unstable and one leg suddenly gave way.
Learner examples
This ladder is unstable, so please be careful.
Ez a létra instabil, ezért kérlek, légy óvatos.
The table is unstable and shakes when I write.
Az asztal instabil, és billeg, amikor írok rajta.
They closed the road because the wall is unstable.
The ground is unstable after the heavy rain.
The shelf is unstable because it is not fixed to the wall.
Common mistake:
Learners sometimes use "broken" instead of "unstable". "Broken" means something does not work at all; "unstable" means it may still work but is not safe or firm and could move or fall.
Meaning
not firmly fixed; may fall
Collocations
unstable ladder
|unstable structure
|unstable surface
|unstable ground
|structurally unstable
|become unstable
Synonyms
unsteady (Focuses more on shaking or not being firm, but less on danger of collapse.)
|
rickety (Informal; suggests weakness from age or poor construction and a high chance of breaking.)
Antonyms
stable (Firm, steady, and not likely to move or fall.)
Themes
safety
|objects
|construction
|daily_life
|housing
Definition
Not firm or safe, and may move or fall down.
Not firmly fixed or supported and therefore likely to move, shake, or fall.
B2
2
Usage pattern:
an unstable [situation/system/condition]
The political situation remains unstable after last year’s election.
A politikai helyzet a tavalyi választás óta továbbra is instabil.
Investors are nervous because of the unstable housing market.
A befektetők aggódnak az instabil lakáspiac miatt.
The region has been economically unstable for decades.
Her income is unstable, so she finds it hard to plan for the future.
The software is still unstable and crashes every few hours.
Learner examples
The weather is unstable in spring.
Tavasszal változékony az időjárás.
His job is unstable, so he is worried about money.
Bizonytalan az állása, ezért aggódik a pénz miatt.
They live in an unstable country with many protests.
The company is unstable and may close next year.
My internet connection is unstable and often stops working.
Common mistake:
Learners sometimes say "unsafe" or "insecure" when they mean "unstable" for markets or situations. "Unsafe" is about danger, and "insecure" is about not feeling safe; "unstable" focuses on frequent or sudden change that makes something less reliable.
Meaning
likely to change suddenly; unreliable
Collocations
unstable economy
|unstable market
|unstable political situation
|unstable government
|unstable weather
|unstable system
Synonyms
volatile (Often used for markets, situations, or personalities that change suddenly and strongly.)
|
inconsistent (Emphasizes not being the same each time, but slightly weaker in feeling than "unstable".)
Antonyms
stable (Not changing much over time and therefore safe and reliable.)
Themes
society
|economics
|politics
|core_vocabulary
Definition
Changing a lot in a way you cannot predict, so it is not safe or reliable.
Likely to change suddenly and unpredictably, and therefore not reliable or secure.
B2
3
Usage pattern:
[someone] is unstable / an unstable [person/personality]
His behavior has become increasingly unstable, and his family is very worried.
A viselkedése egyre kiszámíthatatlanabbá vált, és a családja nagyon aggódik.
The court ordered a psychological evaluation after reports that he was mentally unstable.
A bíróság pszichológiai vizsgálatot rendelt el, miután beszámolók érkeztek arról, hogy a férfi mentálisan instabil.
Growing up with an emotionally unstable parent can be very stressful for children.
The therapist explained that he was not dangerous, just emotionally unstable and in need of support.
Her mood is so unstable that you never know how she will react.
Learner examples
He is unstable and gets angry very quickly.
Labilis, és nagyon hamar dühbe gurul.
She is emotionally unstable after the accident.
A baleset óta érzelmileg labilis.
They think he is mentally unstable and needs help.
Her moods are unstable, and she changes from happy to sad in minutes.
Living with an unstable person can be very hard.
Common mistake:
Calling someone "unstable" is very strong and can sound rude or judgmental. Use it carefully, often in medical, legal, or serious situations. In everyday talk, learners might choose softer words like "very up and down" or "has mood swings" to sound less harsh.
Meaning
emotionally or mentally unreliable
Collocations
emotionally unstable
|mentally unstable
|psychologically unstable
|unstable personality
|mentally unstable person
Synonyms
erratic (Describes behavior that is unpredictable or irregular but sounds less clinical or serious.)
|
disturbed (Suggests serious emotional or mental problems, often used more in medical or formal contexts.)
Antonyms
balanced (Describes a person with steady emotions and reasonable behavior.)
Themes
emotions
|health
Definition
Having very strong mood or behavior changes that make a person hard to trust or feel safe with.
Having emotions, thoughts, or behavior that change suddenly and extremely, often in a way that seems unhealthy or unsafe.
C1
TECHNICAL
4
Usage pattern:
an unstable [compound/isotope/particle]
This compound is highly unstable and must be stored at very low temperatures.
Ez a vegyület rendkívül instabil, és nagyon alacsony hőmérsékleten kell tárolni.
The isotope is too unstable to occur naturally and can only be produced in a lab.
Az izotóp túl instabil ahhoz, hogy a természetben előforduljon, és csak laboratóriumban állítható elő.
As the star ages, its core becomes unstable and eventually collapses.
Above 200°C, the mixture is unstable and will rapidly decompose.
The model shows that the system is dynamically unstable for small perturbations.
Learner examples
The gas is unstable and can explode easily.
A gáz instabil, és könnyen felrobbanhat.
This chemical is unstable in light and should be kept in a dark bottle.
Ez a vegyszer fény hatására instabillá válik, ezért sötét üvegben kell tárolni.
Some atoms are unstable and give off radiation.
Water is stable, but this other liquid is unstable.
An unstable molecule can change into a new substance.
Meaning
chemically or physically likely to change
Collocations
unstable compound
|unstable isotope
|unstable nucleus
|unstable molecule
|thermally unstable
|dynamically unstable
Synonyms
reactive (Stresses readiness to react with other substances, not all types of physical instability.)
Antonyms
stable (In chemistry and physics, not likely to change, react, or break down under normal conditions.)
Themes
science
|chemistry
|physics
Definition
In chemistry or physics, easy to change into something else, for example by reacting or breaking apart.
In science, likely to change into a different chemical or physical state, especially by reacting, decomposing, or breaking down.
Grammar
Dictionary form
unstable
IPA
GB/ʌnstˈeɪbəl/
US/ʌnstˈeɪbəl/
Syllables & stress
un - stable (2 syllables)
Stress on 2nd syllable (stable)
Word forms
Adjective
- Base: unstable
Word family
Negative and opposite forms
instability
noun B2
Advanced or less common
stabilization
noun
destabilize
verb C1
Expressions
an unstable situation
1/ən ʌnstˈeɪbəl sˌɪt͡ʃuˈeɪʃən/
fixed phrase
situation likely to change or worsen
A situation that can easily change in a bad way, for example into conflict or problems.
Examples
- It’s an unstable situation, and small mistakes could start a crisis.
- They entered an unstable situation without a clear plan.
- Negotiators are trying to calm an unstable situation at the border.
mentally unstable
1/mˈɛntəli ʌnstˈeɪbəl/
fixed phrase
having serious mental health issues
Having strong mental health problems that cause unusual or unsafe thoughts or actions.
Examples
- The court ruled that he was mentally unstable at the time of the crime.
- Neighbors had long suspected that the man was mentally unstable.
- They argued that she was mentally unstable and needed treatment, not prison.
politically unstable
1/pəlˈɪtɪkəli ʌnstˈeɪbəl/
fixed phrase
having unstable politics or government
Having many sudden changes in leaders or government, often with protests or conflict.
Examples
- The country has been politically unstable since the military coup.
- Investors are cautious about doing business in politically unstable regions.
- Tourists are advised to avoid politically unstable areas during elections.
unstable economy
1/ʌnstˈeɪbəl ɪkˈɑnəmi/
fixed phrase
economy with many sudden changes
An economy that goes up and down a lot, so people and businesses cannot plan safely.
Examples
- Many families are struggling in the country’s unstable economy.
- Investors dislike an unstable economy because it raises their risk.
- An unstable economy can quickly turn a small problem into a big crisis.
unstable ground
1/ʌnstˈeɪbəl ɡɹˈaʊnd/
fixed phrase
ground that may move or collapse
Ground that is not firm and may move, break, or fall down.
Examples
- The rescue team could not get closer because of the unstable ground.
- Building on unstable ground can be very dangerous.
- Heavy rain has turned the hillside into unstable ground.
unstable internet connection
1/ʌnstˈeɪbəl ˈɪntɚnˌɛt kənˈɛkʃən/
fixed phrase
internet that keeps cutting out
An internet connection that often stops working or changes speed suddenly.
Examples
- I keep dropping out of the call because of my unstable internet connection.
- Online classes are difficult in rural areas with unstable internet connections.
- The video quality is poor due to an unstable internet connection.
emotionally unstable
1/ɪmˈoʊʃnəli ʌnstˈeɪbəl/
fixed phrase
having changeable or extreme emotions
Having strong mood changes and finding it hard to control feelings.
Examples
- He became emotionally unstable after losing his job.
- After the accident, he became emotionally unstable and needed counseling.
- The doctor said she was emotionally unstable and needed support.
- The report described her as emotionally unstable and easily upset.
- Growing up with an emotionally unstable parent can be very stressful.
- Growing up with an emotionally unstable parent can be confusing for a child.