suppose

suppose — verb

1. to have an opinion that something is probably true or will happen, based on the

1.verbtransitive / intransitiveB1
Definition

to have an opinion that something is probably true or will happen, based on the information available but without full certainty

Example

Anong supposed the train would arrive on time, but it was delayed by an hour.

suppose + that-clause for an assumption

The scientists supposed the data was accurate enough to publish.

passive: be supposed to be [adjective]

Common collocations
  • suppose (that)
  • I suppose so
  • commonly supposed
  • reasonably supposed
Synonyms
  • assume

    stronger — taking something for granted without evidence, often as a starting point for reasoning

  • presume

    stronger — based on reasonable probability rather than mere guesswork

  • guess

    less formal and more uncertain — based on little or no evidence

Antonyms
  • know

    to be certain of something through proof or experience

Grammar Patterns

suppose + that-clause

suppose + so

Usage Note

The passive construction 'be supposed to' has a separate meaning related to obligation or expectation (e.g. 'You are supposed to wear a helmet'). Do not confuse it with this active sense.

Common Mistakes

I am suppose to call him.
I am supposed to call him.
the past participle 'supposed' is needed after 'be' in the passive. 'Suppose' alone is active.
I suppose it is true, but I have no evidence.
I assume it is true, but I have no evidence.
'suppose' is more tentative and suggests some basis; 'assume' works better when there is no evidence at all.

2. used to say that you accept something as true or unavoidable, even though you wi

2.verbtransitiveB2
Definition

used to say that you accept something as true or unavoidable, even though you wish it were not so

Example

Jabari supposed they would have to accept that the project had failed.

third person: supposed + would have to

Eli supposed they would need to sell the house after all.

Common collocations
  • I suppose
  • suppose + have to
  • suppose + would
Synonyms
  • guess

    less formal and less emotionally charged — simply estimating rather than reluctantly accepting

  • expect

    more neutral — implies prediction without the sense of reluctance

Grammar Patterns

I suppose + that-clause (reluctant)

subject + supposed + would/could

Usage Note

Common in first-person 'I suppose...' to soften an unpleasant admission. The tone is reluctant rather than neutral. In third person, the reluctance is often conveyed through context such as 'after all' or 'would have to'.

3. used to express anger or irritation, especially by suggesting that someone belie

3.verbtransitiveB2
Definition

used to express anger or irritation, especially by suggesting that someone believes something unreasonable

Example

I suppose you think you are too good to help with the dishes.

rhetorical: I suppose you think…

'So I suppose you expect me to work late without extra pay,' Esteban told his boss.

clause-initial So I suppose you expect…

Common collocations
  • I suppose + rhetorical question
  • I suppose you think
Synonyms
  • I gather

    less confrontational — implies deduction rather than annoyance

Grammar Patterns

I suppose + you + think/expect (rhetorical)

Usage Note

Always in first person 'I suppose...' and followed by a rhetorical claim that the speaker finds unreasonable. The tone is sarcastic or confrontational — never neutral. Common in spoken arguments.

Common Mistakes

Using this sense in formal writing: 'I suppose you think the report is fine.' (sarcastic tone is inappropriate for business reports)
It seems you are satisfied with the report.

4. used to show that you accept someone else's idea or point of view, even though y

4.verbtransitive / intransitiveB2
Definition

used to show that you accept someone else's idea or point of view, even though you are not completely convinced or happy about it

Example

'Maybe you are right,' said Anong. 'I suppose so,' replied Caleb.

short response: I suppose so

I suppose the cheaper option makes more sense with our budget.

Common collocations
  • I suppose so
  • I suppose you are right
Synonyms
  • I guess

    more casual and common in American English; slightly less reluctant in tone

  • concede

    more formal — used in debates and formal discussions

Antonyms
  • deny

    to state that something is not true

Grammar Patterns

I suppose so

I suppose + clause (reluctant agreement)

Usage Note

Often appears as the short response 'I suppose so' or 'I suppose you are right.' Unlike sense 2 (UNWELCOME TRUTH), the focus here is on conceding a point in an argument, not on reluctantly facing an unpleasant fact.

5. used to make a suggestion or request less direct and therefore more polite

5.verbtransitiveB2
Definition

used to make a suggestion or request less direct and therefore more polite

Example

I suppose we could take a short break now and finish later.

I suppose we could (polite suggestion)

I suppose you could help me carry these boxes upstairs.

I suppose you could (polite request)

Common collocations
  • I suppose we could
  • suppose I
  • I suppose you could
Synonyms
  • perhaps

    adverb used to soften suggestions; not a verb but serves a similar polite function

  • maybe we could

    more casual and slightly less tentative

Grammar Patterns

I suppose we could…

Suppose I/we… (direct polite offer)

I suppose you could…

Usage Note

The structure 'Suppose I/we…' (without 'I' before 'suppose') functions as a direct polite suggestion. The full 'I suppose we could…' form is softer and more hesitant. Both are common in British English for polite requests.

Common Mistakes

Suppose you help me?' (sounds incomplete)
I suppose you could help me.' or 'Suppose I help you.
the polite suggestion structure works best with 'I' or 'we' as the subject of 'suppose'.

6. to require a particular situation or fact to be true as a necessary basis for so

6.verbtransitiveB2
Definition

to require a particular situation or fact to be true as a necessary basis for something else to make sense or work properly

Example

The plan supposes that everyone will agree to work on Sunday.

abstract subject: The plan supposes that…

This recipe supposes you have a food processor at home.

Common collocations
  • plan supposes
  • theory supposes
  • budget supposes
Synonyms
  • presuppose

    more formal and technical; implies a logical or philosophical precondition

  • require

    more general — can apply to people, things, or conditions

  • take for granted

    more informal — assuming something without checking

Grammar Patterns

plan / theory / budget / rule supposes that…

Usage Note

Unlike the other senses, the subject here is always an abstract thing (plan, theory, budget, system) — never a person. This sense is formal and common in academic, technical, and business contexts.

Common Mistakes

I suppose your help.' (using this sense with a person as subject)
The plan supposes your help.
this sense requires an abstract subject.
Idioms

be supposed to do/be something

idiom

This phrase means that someone expects you to do something because of a rule, a plan, or a usual way of doing things.

Maya is supposed to finish her homework before dinner.

Are we supposed to wear formal clothes to the party?

not be supposed to do something

idiom

This phrase means that you are not allowed to do something.

You are not supposed to park your car in front of the fire station.

Diego knew he was not supposed to open the door for strangers.

suppose — conjunction

Word family

Synonym discussion

Sense: verb/1

All four words involve forming an opinion without complete proof, but they differ in confidence and basis. 'Assume' means taking something for granted without evidence, often as a starting point for reasoning. 'Presume' carries stronger confidence based on probability or reasonable grounds — you presume something when it seems logical given what you know. 'Suppose' is lighter and more tentative: it puts forward a possibility for consideration, often with less certainty than 'presume.' 'Guess' is the least formal and most uncertain, based on little or no evidence — you guess the answer when you have no real data. 'Speculate' involves thinking about possibilities with even less factual support, typically about future events. For example: 'I assume the shop is open (taking it for granted). I presume you have finished (strong expectation). I suppose we could take the train (tentative suggestion). I guess it costs about fifty dollars (rough estimate). Investors speculate about rising prices (uncertain future prediction).'

assume ↗presume ↗guess ↗speculate ↗

Common collocations

Nouns

  • scientists suppose
  • plan supposes
  • theory supposes
  • budget supposes

Adverbs

Phrases

  • I suppose
  • let us suppose
  • suppose that
  • I suppose so

Etymology

LatinOld FrenchMiddle EnglishEnglish

The word 'suppose' comes from Old French 'supposer,' which was formed by blending Latin 'supponere' (to put under, to substitute) with the French verb 'poser' (to put, to place). The Latin 'supponere' itself breaks down into 'sub-' (under) and 'ponere' (to put, to place). Its original meaning was 'to put something under something else' or 'to substitute,' which later shifted to mean 'to assume as a basis of argument' — since putting one idea 'under' another is like treating it as a foundation for further reasoning. This logical sense entered English through French in the 14th century, and by the 16th century it had developed its modern meaning of 'to think something is likely true.'