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

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

From a certain point of view, it makes sense to concentrate the art into discrete thematic galleries, and to treat the space between them as flowing interstitial fluid through which the visitor can meander happily.

From The Wall Street Journal • Oct. 29, 2025

The director also leans nicely into interstitial shots that orient us without attitude, while her choice of music, led by Lesley Barber’s lilting score, is a real mood-setter of romance and melancholy.

From Los Angeles Times • May 2, 2025

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

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