di·la·tion | \dī-ˈlā-shən \

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

Their collective had released only a few songs publicly as of this weekend, but fans got to hear an album's worth of Vernon’s signature falsetto and folktronica dilations combined with Dessner’s guitar and vocals. Erin Richards, Milwaukee Journal Sentinel, "Eaux Claires IV review: Day 1 music," 7 July 2018 Although the patient eventually had her surgery here, the delay resulted in additional uncomfortable dilations in her home state. Nick Manetto, STAT, "Medicaid’s unnecessary barriers delay care for children with complex needs," 1 May 2018 And even after a month of discomfort and blood loss, up to 20 percent of women will still have pregnancy tissue lingering in the uterus and require a dilation and evacuation. Dorothy Novick, STAT, "FDA shouldn’t allow politics to hurt women suffering miscarriage," 22 June 2018 As further research would soon reveal, the primary cause of migraine pain is not dilation of blood vessels in the head, and the primary factor by which triptans help is not by constricting those vessels. R. Allan Purdy, Scientific American, "Can Anything Stop My Migraine?," 1 May 2017 Once one of these three methods is performed, the dilation and evacuation procedure can then be used, the state said. Bill Rankin, ajc, "Appeals court seems unlikely to uphold ‘fetal demise’ abortion law," 25 May 2018 The family has been monitoring the dilation of her cervix more closely than the weather forecast, hoping that Coy may wait until at least the day after the funeral. USA TODAY, "Relatives hold funeral for Iowa family found dead in Mexico as questions remain," 31 Mar. 2018 Humphrey was working under the assumption that the dilation of the blood vessels inside and outside the skull was responsible for migraine headaches and that drugs that could bind to serotonin receptors might provide relief. R. Allan Purdy, Scientific American, "Can Anything Stop My Migraine?," 1 May 2017 On March 27, the Kentucky House of Representatives passed a bill banning dilation and evacuation, a procedure often used in second-trimester abortions, if a patient is more than about 11 weeks pregnant. Anna North, Vox, "How Trump helped inspire a wave of strict new abortion laws," 3 May 2018

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

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di·la·tion | \dī-ˈlā-shən \

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

Comments on dilation

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exaggeratedly or childishly emotional

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