outermost

American  

[ou-ter-mohst, -muhst] / ˈaʊ tərˌmoʊst, -məst /

adjective

1. farthest out; remotest from the interior or center.

   the outermost limits.

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outermost British  

/ ˈaʊtəˌməʊst /

adjective

1. furthest from the centre or middle; outmost

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Etymology

Origin of outermost

Middle English word dating back to 1350–1400; outer, -most

Example Sentences

The astronauts will then have the chance to study the solar corona, the outermost layer of the Sun's atmosphere, which will become visible as a sort of glowing halo.

From Barron's • Apr. 5, 2026

Past conflicts—due largely to a considerable lag between U.S. doctrine and technology—began with the outermost defensive ring and painfully worked toward the innermost ring of the capital, he wrote.

From The Wall Street Journal • Mar. 30, 2026

That’s when the star goes supernova, which we can detect as soon as the bounced off material breaks through the star's outermost layer — we call this the shock breakout.

From Space Scoop • Nov. 28, 2025

Greenland’s forbidding environment, at the outermost boundary of the European and North American world, have long made it one of the strangest places on earth.

From Salon • Dec. 29, 2024

With five Euclidean solids to play with, and one sphere inside the innermost solid as well as one outside the outermost solid, this defined six spheres—one for each of the orbits of the planets.

From "The Scientists" by John Gribbin