di·​la·​tion | \ dī-ˈlā-shən How to pronounce dilation (audio) \

Definition of dilation

1 : the act or action of dilating : the state of being dilated : expansion, dilatation
2 : the action of stretching or enlarging an organ or part of the body

Examples of dilation in a Sentence

Recent Examples on the Web In theory, Hunter said, the heat itself could be beneficial, since sauna therapy has been shown to improve blood vessel dilation and blood pressure. Amy Norton, chicagotribune.com, "‘Hot’ yoga, hula dance your way to healthy blood pressure," 16 Sep. 2019 Drug Recognition Experts, or DREs, are officers who are trained to run additional field tests designed to detect drug use, such as taking the driver’s blood pressure, temperature and pulse, and testing eye tracking and pupil dilation. Robert Mccoppin, chicagotribune.com, "Cops want to know who’s driving while stoned. Tests are being developed, but level of impairment after smoking weed is still hard to measure.," 21 Oct. 2019 Chemokines can cause tissue swelling, blood vessel dilation—manifesting as sunburn redness—pain, and even a few systemic symptoms. Tiffany Dodson, SELF, "9 Soothing Products People Swear By for Sunburn Relief," 25 May 2019 Meanwhile, Skow used a remote control to move the high-resolution camera in Montana, zooming in to check the patient's pupils for dilation and using a microphone to listen for breathing sounds. Eli Saslow, chicagotribune.com, "The most remote emergency room," 18 Nov. 2019 Use one time-dilation, one Force-pull, and one strong attack, and... that's it for at least 10 seconds. Sam Machkovech, Ars Technica, "Jedi: Fallen Order game review: More like, the Force goes back to sleep," 14 Nov. 2019 Meanwhile, Tuck was shown in her hospital bed with assistants lifting her legs as the doctor monitored her dilation. Lydia Price, PEOPLE.com, "From Shay Mitchell to Kourtney Kardashian, 9 Celeb Moms Who Shared Dramatic Delivery Room Videos," 23 Oct. 2019 The dilation and evacuation procedure accounted for 27 of the 7,778 abortions performed in Indiana during 2017, amounting to 0.35 percent, according to an Indiana State Department of Health report. CBS News, "Federal judge blocks Indiana's second-trimester abortion ban," 28 June 2019 For Goltman, this added support to the theory, first proposed during the 19th century, that migraine headache must be vascular in origin and characterized by dilation of the blood vessels during the attack. Katherine Foxhall, Time, "How A Nurse With a Hole in Her Skull Changed The Medical History of Migraines," 18 June 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'dilation.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of dilation

15th century, in the meaning defined at sense 1

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Time Traveler for dilation

Time Traveler

The first known use of dilation was in the 15th century

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Statistics for dilation

Last Updated

9 May 2020

Cite this Entry

“Dilation.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/dilation. Accessed 25 May. 2020.

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di·​la·​tion | \ dī-ˈlā-shən How to pronounce dilation (audio) \

Medical Definition of dilation

1 : the state of being dilated : dilatation
2 : the action of stretching or enlarging an organ or part of the body cervical dilation dilation of the pupil with atropine

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More from Merriam-Webster on dilation

Thesaurus: All synonyms and antonyms for dilation

Rhyming Dictionary: Words that rhyme with dilation

Nglish: Translation of dilation for Spanish Speakers

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