supposed

supposed — adjective

1. used to say that, according to a rule, an agreement, or what people expect, some

1.adjectiveA2
Definition

used to say that, according to a rule, an agreement, or what people expect, someone should or must do something — often used when the person may not actually do it.

Example

Before nine o'clock, the children are supposed to be in bed on school nights.

be supposed to + infinitive (obligation by rule)

You are not supposed to use your phone during the test.

negative: be not supposed to (prohibition)

Common collocations
  • supposed to be
  • supposed to do
  • supposed to have
  • supposed to go
  • not supposed to
Synonyms
  • required

    more formal and stronger; implies a clear rule or command

  • expected

    similar in strength; focuses on what others believe you will do

  • meant to

    less formal; common in everyday speech

Antonyms

Grammar Patterns

be supposed to + infinitive

Usage Note

The verb 'be' is required before 'supposed to'. This construction is weaker than 'must' (more like an expectation than a firm order) and stronger than 'should' (more like a rule than a suggestion). The negative form 'not supposed to' means 'not allowed to'.

Common Mistakes

I supposed to go to school yesterday.
I was supposed to go to school yesterday.
The verb 'be' (am/is/are/was/were) must always come before 'supposed to'.
You are suppose to wait here.
You are supposed to wait here.
The '-d' at the end of 'supposed' is never dropped, even though it sounds like 'suppose' in fast speech.

2. used to describe the function or purpose that something was designed or expected

2.adjectiveB1
Definition

used to describe the function or purpose that something was designed or expected to have, especially when the real result is different from what was planned.

Example

This button is supposed to open the gate, but it has not worked for weeks.

be supposed to + infinitive (intended function vs reality)

The new medicine is supposed to help people sleep without any side effects.

Common collocations
  • supposed to work
  • supposed to help
  • supposed to last
  • supposed to end
  • supposed to lead to
Synonyms
  • intended

    more formal; focuses on the original design or plan

  • meant

    very similar; the most common alternative in everyday speech

  • designed

    emphasizes that the purpose was built into the thing on purpose

Antonyms

Grammar Patterns

be supposed to + infinitive

Usage Note

Distinguish from sense 1 (DUTY): this sense focuses on design, purpose, or expected outcome rather than obligation. If you say 'the machine is supposed to print labels', you describe its intended function — not a duty. The contrast between expectation and reality is often made explicit with 'but'.

Common Mistakes

❌ 'He is supposed to be an engineer.' (when meaning he is believed to be — use sense 3 instead). — This sentence is ambiguous between 'expected to become' (sense 2) and 'allegedly is' (sense 3). Add context to make the meaning clear.

3. described or believed by a lot of people as being a particular kind of person or

3.adjectiveB2
Definition

described or believed by a lot of people as being a particular kind of person or thing, when the speaker doubts or does not accept that this is true — used before a noun.

Example

The supposed expert could not answer a single question from the audience.

prenominal: supposed + noun (doubt about claimed identity)

Niran spent a lot on a supposed cure for back pain that did nothing.

Common collocations
  • supposed expert
  • supposed friend
  • supposed cure
  • supposed miracle
  • supposed profits
Synonyms
  • alleged

    more formal; often used in legal or news contexts

  • so-called

    informal; strongly expresses the speaker's dismissal

  • reputed

    less common; implies general belief without the speaker's strong doubt

  • would-be

    used for people trying to be something they are not

Antonyms
  • genuine

    real and authentic, not claimed or pretended

  • proven

    shown to be true with evidence

  • actual

    real, as opposed to what people claim

Grammar Patterns

supposed + noun

Usage Note

Pronunciation differs from senses 1 and 2. Here 'supposed' is pronounced /səˈpoʊzɪd/ (three syllables: sup-po-zed). In 'be supposed to' (senses 1 & 2), it is pronounced /səˈpoʊst/ (two syllables: sup-post). This sense always appears directly before a noun, never in 'be supposed to' construction.

Common Mistakes

The expert is supposed.
The supposed expert could not help.
'Supposed' in this sense cannot stand alone after a verb; it must be placed directly before the noun it describes.

❌ Using 'supposed' in this sense without expressing doubt. The word carries the speaker's disbelief — do not use it for claims you agree with.

Word family

Synonym discussion

Sense: adjective/3

All four words express doubt about a claim, but they differ in tone and context. 'Alleged' is the most formal and neutral — it is common in news reports and legal settings ('the alleged thief'), where the speaker reports an accusation without taking sides. 'So-called' is dismissive and informal: calling someone a 'so-called friend' implies the speaker thinks the label is undeserved. 'Reputed' is less common and weaker in doubt — it can be used for things generally believed without the speaker's strong scepticism ('a reputed expert'). 'Would-be' applies only to people who try but fail to become something ('a would-be singer'). For everyday doubt with clear scepticism, 'supposed' and 'so-called' are the most natural choices. Use 'alleged' in formal or written contexts where you want to avoid sounding emotional.

allegedso-called ↗reputedwould-be

Common collocations

Phrases

  • be supposed to

Prepositions

Etymology

LatinFrenchEnglish

'Supposed' comes from the past participle of the verb 'suppose', which entered English from Old French 'supposer' in the 14th century. The French word came from Latin 'supponere' (sub- 'under' + ponere 'to put'), which originally meant 'to put under' or 'to substitute'. Over time the meaning shifted from 'to substitute something falsely' to 'to assume as a basis for reasoning'. The adjective 'supposed' (meaning 'alleged') appeared in the 1500s, while the 'be supposed to' construction (expressing obligation or expectation) developed in the 1600s–1700s.