diagonal: meaning, definition, pronunciation and examples
B1Neutral, used across formal, academic, and everyday contexts.
Quick answer
What does “diagonal” mean?
A straight line joining two non-adjacent corners or vertices of a polygon or polyhedron, or describing something slanting at an angle.
Audio
Pronunciation
Definition
Meaning and Definition
A straight line joining two non-adjacent corners or vertices of a polygon or polyhedron, or describing something slanting at an angle.
Can describe a pattern of lines crossing at an angle, a chess piece's movement, or metaphorically a non-linear or indirect approach.
Dialectal Variation
British vs American Usage
Differences
Minimal. 'Diagonal' is standard in both. Spelling is identical. Usage in contexts like 'cut on the diagonal' (more common in US cooking) vs 'cut diagonally' (slightly more common in UK).
Connotations
Identical. Carries mathematical, design, and spatial connotations in both varieties.
Frequency
Slightly higher frequency in US English in cooking contexts (e.g., 'slice diagonally').
Grammar
How to Use “diagonal” in a Sentence
The diagonal of [a square/rectangle][a line/street] runs diagonallycut [something] diagonallyVocabulary
Collocations
Examples
Examples of “diagonal” in a Sentence
noun
British English
- The painter drew a bold diagonal across the canvas.
- The bishop moved along the long diagonal.
American English
- Calculate the length of the diagonal of the square.
- She cut the sandwiches on the diagonal for a nicer presentation.
Usage
Meaning in Context
Business
Used in data analysis (e.g., 'diagonal matrix in statistics'), design, and strategy ('a diagonal move in the market').
Academic
Core term in geometry, linear algebra, and art/design theory.
Everyday
Describing cutting food, walking across a field, or striped clothing.
Technical
Precise geometric term; used in engineering, computer graphics (e.g., 'diagonal resolution'), and textile design.
Vocabulary
Synonyms of “diagonal”
Vocabulary
Antonyms of “diagonal”
Watch out
Common Mistakes When Using “diagonal”
- Using 'diagonal' as a verb (e.g., 'He diagonalled the square' – incorrect). The correct verb form is 'to cut/move/run diagonally'. Confusing 'diagonal' (noun/adjective) with 'diagonally' (adverb).
FAQ
Frequently Asked Questions
No, 'diagonal' is not a standard verb. Use 'cut diagonally', 'move diagonally', or 'run diagonally'.
In geometry, they are often synonymous. However, 'oblique' can describe any angle not 90°, while 'diagonal' specifically connects non-adjacent corners. 'Oblique' is also more common in general language for 'indirect' (e.g., an oblique remark).
Stress the second syllable: dy-AG-uh-nul (/daɪˈæɡ.ən.əl/). The 'g' is a hard /g/ sound.
It is the diagonal from the top-left to the bottom-right corner of a square matrix, containing elements where the row and column indices are equal.
A straight line joining two non-adjacent corners or vertices of a polygon or polyhedron, or describing something slanting at an angle.
Diagonal is usually neutral, used across formal, academic, and everyday contexts. in register.
Phrases
Idioms & Phrases
- “on the diagonal”
- “the long diagonal (chess)”
Learning
Memory Aids
Mnemonic
Think of 'DIAGonal' – it goes from one 'DIAG'onal (diagnosis? No, DIAGonal!) to the opposite corner.
Conceptual Metaphor
A diagonal is often a shortcut (spatially or in thinking), representing efficiency, dynamism, or an alternative path.
Practice
Quiz
In which context is 'diagonal' used incorrectly?