impossible

impossible — adjective

1. When an action, event, or result is described as impossible, no person or method

1.adjectiveA2
Definition

When an action, event, or result is described as impossible, no person or method can make it happen, achieve it, or bring it about under any circumstances.

Example

It is impossible for Bao to finish the report by five — he needs more data.

impossible for + person + to-infinitive

Greta found it impossible to sleep the night before her final exams.

found it impossible to do something

Common collocations
  • impossible task
  • impossible dream
  • virtually impossible
  • almost impossible
  • prove impossible
Synonyms
  • not possible

    a longer but more transparent phrase; common in spoken English

  • out of the question

    more informal and emphatic; suggests the idea is completely rejected

  • unattainable

    focuses on the goal being unreachable; narrower in scope

Antonyms
  • possible

    the direct opposite; something can happen or be done

  • feasible

    something is achievable or practical

Grammar Patterns

it is impossible (for someone) to do something

something + linking verb + impossible

find/consider/think + something + impossible

Usage Note

Commonly appears in two main patterns: (1) 'it is impossible (for someone) to do something', where 'it' refers forward to the infinitive clause; and (2) with a linking verb ('seems', 'became', 'is') describing the subject directly. The second pattern cannot take a following infinitive without restructuring.

Common Mistakes

It is impossible Bao finishes the report by five.
It is impossible for Bao to finish the report by five.
After 'it is impossible', use 'for + person + to-infinitive', not a 'that'-clause with a finite verb.

2. When a situation, position, or task is so full of problems that handling it beco

2.adjectiveB2
Definition

When a situation, position, or task is so full of problems that handling it becomes nearly unbearable, we describe it as impossible.

Example

The company faced an impossible situation when the manager and accountant quit on the same day.

impossible situation (collocation for dilemma contexts)

Madison faced an impossible position: keep her job or move abroad with her partner.

impossible position (forced-choice context)

Common collocations
  • impossible situation
  • impossible position
  • impossible task
  • impossible choice
Synonyms
  • hopeless

    adds a feeling of despair; less formal

  • untenable

    more formal; used for positions or arguments that cannot be maintained

Antonyms

Grammar Patterns

an impossible + noun (situation / position / task / choice)

make + something + impossible

Usage Note

This sense modifies nouns like 'situation', 'position', 'task', and 'choice'. It does not describe a person's character (see sense 3). Unlike sense 1, this meaning does not claim that something cannot be done at all — only that the difficulty is extreme.

Common Mistakes

The meeting schedule was impossible.' (when meaning just 'difficult' — ambiguous with sense 1)
We were in an impossible meeting situation, with three urgent deadlines at once.
Using 'impossible situation' or 'impossible position' makes the sense clear.

3. Used to describe a person whose behavior is so unreasonable, stubborn, or annoyi

3.adjectiveB2
Definition

Used to describe a person whose behavior is so unreasonable, stubborn, or annoying that it is nearly impossible for others to deal with or live alongside them.

Example

Vivek's roommate is impossible — he leaves dirty dishes everywhere and never pays his bills.

person + is impossible (describing ongoing difficult behavior)

Bao's grandfather became impossible after his illness, refusing to take any medicine the doctor prescribed.

Common collocations
  • being impossible
  • absolutely impossible
Synonyms
Antonyms
  • easygoing

    someone who is relaxed and flexible

  • reasonable

    someone who listens to others and behaves sensibly

Grammar Patterns

someone + is + impossible

someone + is being + impossible

Usage Note

Unlike sense 2, this sense applies to people. Using 'is being impossible' (the progressive form) signals that the behavior is temporary, not a permanent personality trait. This sense is informal and should be avoided in formal or professional writing.

Common Mistakes

My boss is an impossible person.' (grammatically possible but sounds like a permanent judgment)
My boss is being impossible today.
The progressive form makes it clear you mean the current behavior, not the person's character.
Idioms

mission impossible

idiom

A task that is very hard or cannot be done.

Fixing this old car in one day is mission impossible.

Do you think climbing that mountain alone is mission impossible?

impossible — noun

Word family

Synonym discussion

Sense: adjective/1

These four expressions all describe something that cannot happen or be done, but they differ in strength, register, and implied reason. 'Impossible' (A2) is the broadest and most neutral word — it simply states that something cannot be done by anyone under any circumstances. 'Out of the question' (B1) is more informal and carries a sense of rejection: the idea is not even worth discussing. 'Unattainable' (B2) is narrower — it focuses on goals or achievements that lie beyond reach, often due to personal limitations rather than external impossibility. 'Not feasible' (B2) is a practical, factual assessment common in business and planning contexts: a plan that is not feasible is not practical or cost-effective, though it might be theoretically possible. Compare: 'It is impossible to travel faster than light' (physical law); 'Buying a private jet is out of the question for our family' (rejection of the idea); 'An Olympic gold medal seemed unattainable to the young swimmer' (personal limitation); 'The proposal is not feasible given our current budget' (practical constraint).

impossible ↗out of the question ↗unattainablenot feasible

Common collocations

Nouns

Adverbs

Phrases

  • make it impossible
  • find it impossible
  • prove impossible
  • seem impossible
  • render something impossible

Prepositions

Etymology

LatinFrenchEnglish

From Latin 'impossibilis', made up of the negative prefix 'in-' (not) and 'possibilis' (that can be done), which itself comes from 'posse' (to be able). The word entered English through Old French 'impossible' in the 14th century. Over time, the sense broadened from 'physically not possible' to also include social and practical difficulty.