adamantine

American  

[ad-uh-man-teen, -tin, -tahyn] / ˌæd əˈmæn tin, -tɪn, -taɪn /

adjective

1. utterly unyielding or firm in attitude or opinion.

2. too hard to cut, break, or pierce.

3. like a diamond in luster.

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adamantine British  

/ ˌædəˈmæntaɪn /

adjective

1. very hard; unbreakable or unyielding

2. having the lustre of a diamond

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Etymology

Origin of adamantine

First recorded in 1200–1250; Middle English, from Latin adamantinus, from Greek adamántinos see adamant, -ine ¹

Explanation

Something adamantine is unbreakable. Adamantine is often used in a figurative way. If you’re bound by adamantine chains, get comfy because you’re not breaking free! When someone is adamant, the person won't budge or yield. Anything adamantine is pretty much unbreakable and invulnerable. Adamantine substances also tend to be bright and shiny like diamonds. When used figuratively, adamantine can describe something unbreakable, like the adamantine will of a marathon runner.

Example Sentences

Adamantine Bouille's look alters not; yet the word Halt is given: gladder moment he never saw.

From The French Revolution by Carlyle, Thomas

Adamantine as was the lichen-covered heap of granite, it was of far more mutable a quality than were the dispositions of those who had so stubbornly let it fall into decay.

From The Wall Between by Bassett, Sara Ware

The Adamantine Fortress When a man has once deeply wounded a woman's pride, he may just as well give up his hope of winning her.

From The Spinster Book by Reed, Myrtle

Adamantine clinkers, made of gault clay, are much used; they must have chamfered edges, otherwise they make too smooth a floor for a stable.

From Scientific American Supplement, No. 601, July 9, 1887 by Various

Milton indeed has his Adamantine chains and penal fire, and A dungeon horrible on all sides round.

From Amenities of Literature Consisting of Sketches and Characters of English Literature by Disraeli, Isaac