confound

confound — verb

1. to cause someone to feel completely confused and shocked because something unexp

1.verbtransitiveC1
Definition

to cause someone to feel completely confused and shocked because something unexpected happens that they cannot understand or explain

Example

The sudden change in company policy confounded everyone in the office.

passive-like use: confounded + everyone as object

Eri's unexpected decision to quit her job confounded her colleagues.

confound + someone's decision as subject

Common collocations
  • confound expectations
  • confound critics
  • confound the experts
  • confound observers
Synonyms
  • perplex

    similar meaning but without the element of shock; 'perplex' is purely about confusion

  • bewilder

    stronger sense of being lost or unable to think clearly; less formal than confound

  • dumbfound

    emphasises the surprise/astonishment element; more informal and vivid

Antonyms
  • clarify

    to make something clear and understandable, the opposite of confusing

Grammar Patterns

confound + someone

be confounded by + something

Usage Note

Frequently used in the passive voice (be confounded by). The subject of the active form is typically an event, situation, or piece of information — not a person trying to confuse someone on purpose.

Common Mistakes

The teacher confounded the students by giving a hard test.' (sounds like the teacher intended to confuse them).
The students were confounded by the teacher's unusually hard test.
confound describes a reaction to something unexpected, not a deliberate action by a person.

2. to affect the outcome of a scientific study by introducing an unwanted variable,

2.verbtransitiveC2
Definition

to affect the outcome of a scientific study by introducing an unwanted variable, so that it is no longer clear whether the factor being tested actually caused the observed result

Example

Differences in room temperature between the two groups confounded the drug trial results.

confound + [study/results] in active voice

Researchers must control for age and gender, as these factors can confound the findings.

can confound (modal + infinitive)

Common collocations
  • confound the results
  • confound the data
  • confounding variable
  • confounding factor
Synonyms
  • distort

    stronger implication that the result is made incorrect; confound suggests the result becomes unclear rather than wrong

  • skew

    suggests the result is pulled in a particular direction; informal compared to confound

Grammar Patterns

confound + a study / result / experiment

confound + the relationship between X and Y

Usage Note

Almost exclusively used in academic writing about experiments, studies, and statistical analysis. The confounding factor (the unwanted variable) is typically the subject of the active verb. The passive is less common in this sense than in sense 1.

Common Mistakes

The weather confounded our picnic.' (casual context — use sense 1 instead).
Differences in weather confounded the agricultural experiment.
sense 2 requires a formal, scientific context.

3. to prove that a statement, belief, or prediction is false by presenting clear ev

3.verbtransitiveC2
Definition

to prove that a statement, belief, or prediction is false by presenting clear evidence against it

Example

The new fossil discovery confounded the long-held theory about bird evolution.

confound + a theory / belief / claim

Xiu's investigation confounded the popular belief that the painting was a fake.

confound + belief as object

Common collocations
  • confound a theory
  • confound expectations
  • confound critics
  • confound a prediction
Synonyms
  • refute

    more direct synonym; refute focuses on logical argument while confound can include surprising discovery

  • disprove

    more common in everyday language; both mean showing something is false

  • debunk

    informal; used especially for exposing popular myths or false beliefs

Antonyms
  • confirm

    to show that a belief or claim is true

  • support

    to provide evidence in favour of a claim

Grammar Patterns

confound + a claim / belief / argument

confound + someone (their prediction or expectation)

Usage Note

The object is usually an abstract noun (theory, belief, claim, prediction) rather than a person. When a person is the object, the sense overlaps with 'prove someone wrong in their specific claim' rather than 'confuse them.'

Common Mistakes

She confounded his argument by shouting.' (shouting is not evidence).
She confounded his argument with new data from the study.
confound requires evidence, not emotion.
Idioms

confound it/you!

idiom

An expression used when you are annoyed or angry about something or with someone.

Confound it! I left my keys in the car again.

Confound you! Why did you spill coffee on my report?

Word family

  • confounded
    adjectiveC1
  • confoundedly
    adverbC2
  • confounding
    adjectiveC2
  • confoundingly
    adverbC2

Synonym discussion

Sense: verb/1

All four words describe causing confusion, but each emphasises a different shade. CONFOUND (sense 1) combines confusion with shock — the person cannot understand something unexpected or surprising. PERPLEX is purely intellectual: a puzzling problem perplexes you, but it does not shock you. BEWILDER suggests a stronger, more disorienting confusion — a bewildered person feels lost and unable to think clearly at all. DUMPFOUND is more informal and puts the focus on speechless surprise rather than confusion itself. For example, a riddle might perplex you, a plot twist might confound you, a sudden loss might bewilder you, and a magic trick might dumbfound you.

perplexbewilder ↗dumbfoundconfound ↗

Common collocations

Nouns

Adverbs

Phrases

  • confound the odds
  • confound the sceptics

Prepositions

Etymology

LatinFrenchEnglish

From Latin 'confundere' — 'con-' (together) + 'fundere' (to pour). The original image was of pouring two liquids together so they mix and cannot be separated. This 'mixing up' idea gave rise to the sense of confusing people (mixing up their thoughts) and later to proving someone wrong (mixing up their argument).