dilation
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Derived Forms
Inflected Forms
Nouns
Etymology
Origin of dilation
Explanation
Dilation is expansion, usually of an opening such as the pupil. When that happens, your eyes look black and the light comes streaming in. Grab your sunglasses! The word dilation is the noun form of dilate, "to make wider.” Dilation often refers to what happens when a woman goes into labor, and her cervix dilates to let the baby through. Dilation is also used for writing or speech that expands on a topic. Here’s a dilation: funny thing is that the -ate ending of dilate is not a suffix but part of the word, so it should really be dilatation, but no one says it that way.
Vocabulary lists containing dilation
The Woman Warrior
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STAAR Grade 8 Mathematics: Geometry and Measurement, List 1
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Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
See Examples For:
Caffeine temporarily shrinks blood vessels and less dilation means less visible swelling.
From BBC ● Feb. 16, 2026
Not only do we tend to mirror each other’s movements, postures, facial expressions and gestures; we also uncannily sync up our heart rates, blood pressure, pupil dilation and hormonal activity.
From The Wall Street Journal ● Jan. 22, 2026
Time itself passes differently at such distances -- a phenomenon known as cosmological time dilation.
From Science Daily ● Nov. 7, 2025
According to the complaint, the patient reported to Brock’s office in September 2018 for a dilation and curettage to remove remaining tissues from her uterus.
From Los Angeles Times ● Jun. 13, 2025
“But not to the physical stimulus; you’re not measuring dilation, for instance. It’ll be to the verbal questions; what we call a flinch reaction.”
From "Do Androids Dream of Electric Sheep?" by Philip K. Dick
However, when it comes to problems with angina, the study shows that it is possible to avoid patients coming back for new balloon dilations through preventive treatment.
From Science Daily ● Apr. 8, 2024
Like all beauties, these are dilations of time.
From New York Times ● Mar. 9, 2021
The stopped time of a painting, say, or the dilations of the novel, in which it is possible to see patterns and consequences that are otherwise invisible.
From The Guardian ● Mar. 21, 2020
The results showed that people with consistently larger pupil dilations made the most erratic decisions.
From Forbes ● Sep. 24, 2014
After five years my body became so strong that I could control even the dilations of the pupils inside my irises.
From "The Woman Warrior" by Maxine Hong Kingston
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Get a wordDefinitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
