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 The underlying dispute involves a 2018 Kentucky law that sought to ban the procedure used most commonly in second-trimester abortions, known as dilation and evacuation. Brent Kendall, WSJ, "Supreme Court to Decide if Kentucky Attorney General Can Maintain Abortion-Law Defense," 29 Mar. 2021 House Bill 454 bans a procedure known as dilation and evacuation in which the fetus is removed with instruments, generally after the 14th week of pregnancy. Deborah Yetter, The Courier-Journal, "US Supreme Court to decide whether Daniel Cameron can challenge Kentucky abortion ruling," 29 Mar. 2021 Could a Dexcon create a Progressive Snapshot multi-sensor device for a more comprehensive body screening using temperature, skin tone, urine, saliva, pupil dilation, and facial readings? Stephan Zoder, Forbes, "Are Lockdowns Creating Tomorrow’s Opportunities For Manufacturers," 17 Mar. 2021 Act 45 bans dilation and evacuation, a common procedure for second-trimester abortions. Neal Earley, Arkansas Online, "Laws on abortion again put on hold in Arkansas," 23 Dec. 2020 Computer animation predominates, as does an algorithmic adherence to story mechanics that betrays an unwillingness to risk, even momentarily, the dilation of a young viewer’s attention. Mark O’connell, The New Yorker, "Cartoon Saloon and the New Golden Age of Animation," 11 Dec. 2020 During the sessions, participants' brainwaves and pupil dilation were measured. Popular Science, "Heavy media multitasking might make you more forgetful," 28 Oct. 2020 The statute effectively outlawed the dilation and evacuation procedure, known as D&E, in which doctors open the cervix and remove fetal tissue from the uterus. Kaylee Poche, NOLA.com, "Fifth Circuit Court knocks down Texas abortion ban," 13 Oct. 2020 Beginning August 28, doctors in Arkansas will be prohibited from offering patients dilation and evacuation abortions. Kate Smith, CBS News, "Arkansas to implement first-of-their-kind abortion restrictions later this month," 11 Aug. 2020

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

8 Apr 2021

Cite this Entry

“Dilation.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/dilation. Accessed 15 May. 2021.

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More Definitions for dilation


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

More from Merriam-Webster on dilation

Thesaurus: All synonyms and antonyms for dilation

Nglish: Translation of dilation for Spanish Speakers

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