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90s Slang You Should Know


[dahy-ley-shuh n, di-] /daɪˈleɪ ʃən, dɪ-/
the act of dilating; state of being dilated.
Origin of dilation
First recorded in 1590-1600; dilate + -ion
Related forms
nondilation, noun
overdilation, noun
self-dilation, noun Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2017.
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Examples from the Web for dilation
Historical Examples
  • But the contraction and dilation of her pupils were so swift that no one but an expectant observer would have noted the change.

    The Crime Club William Holt-White
  • White is produced by the dilation, black by the contraction, of the particles of sight.

    Timaeus Plato
  • With what a dilation of spirit the ladies would have told tales of him, Fionn's father.

    Irish Fairy Tales James Stephens
  • Thank Heaven, there is yet no dilation of the pupil; it is not too late!

  • But the violet of her eyes was all but hidden by the dilation of her pupils.

    Zuleika Dobson Max Beerbohm
  • After all, the colony would be but "an extension or dilation of the realm of England."

    Give Me Liberty Thomas J. Wertenbaker
  • This I attributed to the dilation of the air contained in the cellular tissue of the organ as much as to the cold outside.

    Wonderful Balloon Ascents Fulgence Marion
  • Systole and diastole, the contraction and dilation of the heart and arteries.

    Essays Ralph Waldo Emerson
  • The dilation of the air, by virtue of its elastic force, is found to be very surprising.

  • He believed very thoroughly in drainage, and in the dilation of narrow fistulous openings.

    Medieval Medicine James J. (James Joseph) Walsh
Word Origin and History for dilation

1590s, formed from dilate on the mistaken assumption that the -ate in that word was the Latin verbal suffix (it is instead part of the stem); the proper form, dilatation, is older (c.1400).

Online Etymology Dictionary, © 2010 Douglas Harper
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dilation in Medicine

dilation di·la·tion (dī-lā'shən, dĭ-)

  1. The act of expanding or the condition of being expanded.

  2. Dilatation.

The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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dilation in Science
  (dī-lā'shən, dĭ-)   
The widening or stretching of an opening or a hollow structure in the body.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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