interstitial

American  

[in-ter-stish-uhl] / ˌɪn tərˈstɪʃ əl /

adjective

1. pertaining to, situated in, or forming interstices.

2. Anatomy. situated between the cells of a structure or part.

   interstitial tissue.

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noun

1. Crystallography. an imperfection in a crystal caused by the presence of an extra atom in an otherwise complete lattice.

interstitial British  

/ ˌɪntəˈstɪʃəl /

adjective

1. of or relating to an interstice or interstices

2. physics forming or occurring in an interstice

   an interstitial atom

3. chem containing interstitial atoms or ions

   an interstitial compound

4. anatomy zoology occurring in the spaces between organs, tissues, etc

   interstitial cells

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noun

1. chem an atom or ion situated in the interstices of a crystal lattice

Other Word Forms

• interstitially adverb

Etymology

Origin of interstitial

1640–50; < Latin interstiti ( um ) interstice + -al ¹

Example Sentences

Those conditions are pulmonary arterial hypertension and pulmonary hypertension with interstitial lung disease.

From Barron's • Mar. 30, 2026

"Conventionally, lung transplant is reserved for patients who have chronic conditions like interstitial lung disease or cystic fibrosis," said Bharat.

From Science Daily • Mar. 18, 2026

Salmon is married to artist and illustrator Fiona Hawthorne, who previously revealed she was diagnosed with a rare lung condition, interstitial lung disease, which requires her to use an oxygen tank.

From BBC • Jan. 1, 2026

The interstitial world of texts, emails and social-media photographs, neither fully part of the material world nor fully within our own minds, acts as a kind of exteriorized collective imagination.

From The Wall Street Journal • Oct. 30, 2025

They are part of each other, interstitial: lodged between each others cells.

From "Vincent and Theo: The Van Gogh Brothers" by Deborah Heiligman