in·​ter·​sti·​tial | \ˌin-tər-ˈsti-shəl \

Definition of interstitial 

1 : occurring in or being an interval or intervening space or segment : of, relating to, or forming an interstice an interstitial space … the site has been running interstitial ads, which consist of a full page of advertising between editorial pages, for a little more than a year.— Carl Sullivan

2a : situated within but not restricted to or characteristic of a particular organ or tissue used especially of fibrous tissue

b : affecting the interstitial tissues of an organ or part interstitial cystitis

3 : being or relating to a crystalline compound in which usually small atoms or ions of a nonmetal occupy holes between the larger metal atoms or ions in the crystal lattice

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Other Words from interstitial

interstitially \ ˌin-​tər-​ˈsti-​shə-​lē \ adverb

Examples of interstitial in a Sentence

Recent Examples on the Web

In strange interstitial chapters, Kushner also includes short excerpts from the diary of Ted Kaczynski, the Unabomber, which Gordon is reading. Josephine Livingstone, The New Republic, "The bold, vivid worlds of Rachel Kushner’s novels," 7 June 2018 These interstitial monologues were fascinatingly bizarre, full of aimless asides and mildly humorous observations at which the worshipful crowd always laughed slightly louder than was warranted. Terence Cawley,, "At the Wang, a free-wheeling journey through Neil Young’s past," 12 July 2018 If accessing true accu-points allows interstitial fluids to travel throughout the body, that might account for the difference. Katie Heaney, The Cut, "Do We Finally Understand How Acupuncture Works?," 30 Mar. 2018 The best parts of the film come in interstitial shots that establish atmosphere. Josephine Livingstone, The New Republic, "Poor Mary Shelley!," 23 May 2018 Kessler, who turned 70 this year, skipped last year's race after being diagnosed with an interstitial lung disease called chronic hypersensitivity pneumonitis. Beth Bragg, Anchorage Daily News, "Lung disease leaves this 70-year-old breathless, but it won’t keep her out of the Gold Nugget Triathlon," 19 May 2018 Previously, physicians had a somewhat nebulous understanding of the interstitial space, Nathanson said. Rachael Rettner, Scientific American, "Meet Your Interstitium, A Newfound “Organ”," 27 Mar. 2018 The interstitial spaces were originally thought to be dense, connective tissue found surrounding arteries and veins and sitting right below the surface of the skin. Brett Molina, USA TODAY, "Study says we have an undiscovered organ. It's called the interstitium," 28 Mar. 2018 Painful-bladder syndrome Technically known as interstitial cystitis, this condition is what doctors call pain in the bladder with no obvious or identifiable cause. Amanda Macmillan,, "12 Reasons You Might Have Cramps That Have Nothing to Do With Your Period," 27 Mar. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'interstitial.' 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 interstitial

1646, in the meaning defined at sense 1

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Time Traveler for interstitial

The first known use of interstitial was in 1646

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in·​ter·​sti·​tial | \ˌint-ər-ˈstish-əl \

Medical Definition of interstitial 

1 : situated within but not restricted to or characteristic of a particular organ or tissue used especially of fibrous tissue

2 : affecting the interstitial tissues of an organ or part interstitial hepatitis

3 : occurring in the part of a fallopian tube in the wall of the uterus interstitial pregnancy

Other Words from interstitial

interstitially \ -​ə-​lē \ adverb

More from Merriam-Webster on interstitial

See words that rhyme with interstitial

Britannica English: Translation of interstitial for Arabic Speakers

Comments on interstitial

What made you want to look up interstitial? Please tell us where you read or heard it (including the quote, if possible).


playful or foolish behavior

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