congruent

IPA/ˈkɒŋɡruənt/
KK[kˈɔnɡruˌɛnt]IPA/ˈkɑːŋɡruənt/

congruent — adjective

  • congruentpositive
  • more congruentcomparative
  • most congruentsuperlative

1. Being in harmony or alignment with something else, with no clash or contradictio

1.adjectiveB2
Definition

Being in harmony or alignment with something else, with no clash or contradiction between the two.

Example

Dr. Okafor's research findings were congruent with the predictions of the climate model.

congruent with + noun phrase

The company's hiring practices need to be congruent with its stated commitment to diversity.

Common collocations
  • congruent with
  • roughly congruent
  • perfectly congruent
  • culturally congruent
  • morally congruent
  • remain congruent
Synonyms
  • consistent

    The closest everyday synonym; 'consistent' is more common in casual speech, while 'congruent' sounds more formal and precise.

  • compatible

    Emphasises the ability to coexist or work together, whereas 'congruent' stresses logical agreement.

  • harmonious

    Suggests a pleasing or natural fit, often used for aesthetics or personal relationships.

Antonyms
  • incongruent

    Direct opposite; describes things that are out of place or do not match.

  • incompatible

    Stronger sense of conflict — incompatible things cannot coexist at all.

Grammar Patterns

congruent + with + noun phrase

Usage Note

Frequently used with the preposition 'with' to indicate what something agrees with. Common in formal, academic, and business writing.

Common Mistakes

His actions were congruent to his words.
His actions were congruent with his words.
Use 'with', not 'to', after 'congruent' in this sense.

2. Describing two geometric figures that have exactly the same measurements and out

2.adjectiveB2
Definition

Describing two geometric figures that have exactly the same measurements and outline, so that one can be placed perfectly over the other.

Example

Two congruent triangles have identical side lengths and matching interior angles.

attributive: congruent + triangles

Tomás showed that the rotated shape was congruent to the original parallelogram.

congruent to [shape] — alternative preposition

Common collocations
  • congruent triangles
  • congruent shapes
  • congruent figures
  • congruent angles
  • congruent sides
  • congruent polygons
  • congruent to
  • congruent with
  • prove congruent
  • be congruent
  • remain congruent
Synonyms
  • identical

    Less precise than 'congruent' in geometry; 'identical' can also refer to non-measurable similarity.

  • equal

    Often used interchangeably with 'congruent' for line segments and angles, but 'congruent' is the standard term for whole shapes.

Antonyms
  • dissimilar

    Describes shapes that differ in appearance but not necessarily in any measured way.

  • noncongruent

    The technical antonym used in geometry textbooks.

Grammar Patterns

congruent + noun (e.g. congruent triangles)

congruent + with/to + noun phrase

Usage Note

Used almost exclusively in geometry. 'Congruent to' and 'congruent with' are both accepted in mathematical English, though 'to' is more common in British textbooks.

Common Mistakes

These two figures are congruent because they look the same shape.
These two figures are congruent because all corresponding sides and angles are equal.
In geometry, congruent is a precise measurement, not a visual impression.

Word family

Synonym discussion

Sense: adjective/1

These three words all describe positive alignment between two things, but they differ in scope and register. 'Consistent' is the broadest and most neutral — it simply means no contradiction exists (e.g., 'Her voting record is consistent with her stated beliefs'). 'Compatible' emphasises the ability to coexist or function together, often in technical or practical contexts (e.g., 'The software is compatible with both operating systems'). 'Harmonious' goes a step further, suggesting not just the absence of conflict but a pleasing, natural fit — it carries a positive emotional or aesthetic tone (e.g., 'The garden design was harmonious with the surrounding landscape'). 'Congruent' sits closest to 'consistent' but is more formal and precise; it is the preferred term in academic, legal, and scientific writing when exact alignment needs to be stated.

consistent ↗compatible ↗harmonious ↗

Common collocations

Nouns

Adverbs

Phrases

  • be congruent with
  • remain congruent to
  • prove congruent

Prepositions

Etymology

LatinFrenchEnglish

Congruent comes from Latin 'congruentem', the present participle of 'congruere' — meaning 'to come together, agree, correspond'. The Latin word combines 'com-' (together) and 'ruere' (to rush, fall), so the original image was of things 'rushing together' and fitting neatly. It entered English via Old French in the 15th century, first used in geometry and later extended to general agreement.