dilation: meaning, definition, pronunciation and examples
C1Formal; Technical/Medical; Scientific
Quick answer
What does “dilation” mean?
The action or process of becoming wider, larger, or more open.
Audio
Pronunciation
Definition
Meaning and Definition
The action or process of becoming wider, larger, or more open.
The widening of an aperture or lumen in a biological context, or the expansion of time in relativity. In mathematics, a transformation that changes the size of a figure without altering its shape.
Dialectal Variation
British vs American Usage
Differences
Usage is identical across both varieties. The verb form 'dilate' is used more commonly than the noun 'dilation' in everyday speech.
Connotations
Identical. Predominantly technical/medical.
Frequency
Slightly higher frequency in American English due to greater prevalence of medical advertising (e.g., 'dilation and curettage' procedure).
Grammar
How to Use “dilation” in a Sentence
dilation of [NOUN][ADJECTIVE] dilationundergo [NOUN] dilationVocabulary
Collocations
Examples
Examples of “dilation” in a Sentence
verb
British English
- The optician will dilate your pupils for the examination.
- Blood vessels dilate in response to the heat.
American English
- The doctor dilated my pupils before the retinal scan.
- His eyes dilated in the dark room.
Usage
Meaning in Context
Business
Rare. Potentially in metaphorical use: 'the dilation of the market'.
Academic
Common in medical, physics, and mathematics papers.
Everyday
Limited. Primarily in health contexts: 'The optometrist checked my pupil dilation.'
Technical
Primary domain. Precise term in medicine, ophthalmology, cardiology, physics.
Vocabulary
Synonyms of “dilation”
Strong
Neutral
Vocabulary
Antonyms of “dilation”
Watch out
Common Mistakes When Using “dilation”
- Misspelling as 'dialation'.
- Using 'dilation' for a sudden rupture or tear (correct: 'laceration' or 'rupture').
- Confusing 'dilation' (process) with 'diameter' (measurement).
FAQ
Frequently Asked Questions
In most medical contexts, they are interchangeable, though 'dilation' is more common in general English. 'Dilatation' is often found in older or more formal medical texts (e.g., 'dilatation and curettage').
No. Dilation specifically refers to becoming larger or wider. The opposite process is 'contriction' or 'narrowing'.
A concept from Einstein's theory of relativity where time passes at different rates for observers in different gravitational fields or relative velocities. A clock moving fast relative to an observer will be measured to tick slower (dilate).
Not very common. It is primarily a technical term. In everyday life, people are more likely to use phrases like 'getting wider,' 'opening up,' or 'enlarging' unless they are in a specific medical or scientific discussion.
The action or process of becoming wider, larger, or more open.
Dilation is usually formal; technical/medical; scientific in register.
Dilation: in British English it is pronounced /daɪˈleɪ.ʃən/, and in American English it is pronounced /daɪˈleɪ.ʃən/ /dɪˈleɪ.ʃən/. Tap the audio buttons above to hear it.
Phrases
Idioms & Phrases
- “Eyes wide with dilation (descriptive, not fixed idiom)”
Learning
Memory Aids
Mnemonic
Think of a DIAmond getting LARGER – DIA-LATION. Or: 'During an eye exam, my pupils DIE (die) waiting for the LIGHT in DILATION.'
Conceptual Metaphor
TIME IS SPACE (time dilation); OPENNESS IS SIZE (dilation of the cervix for birth); ATTENTION/AWARENESS IS LIGHT (pupil dilation in response to interest or low light).
Practice
Quiz
In which of the following contexts is the term 'dilation' LEAST likely to be used correctly?