adamantine

Synonym of adamant.

[A]t laſt appeer / Hell bounds high reaching to the horrid Roof, / And thrice threefold the Gates; three folds vvere Braſs, / Three iron, three of Adamantine Rock, / Impenitrable, impal'd vvith circling fire, / Yet unconsum'd.

Synonym of adamant.

adamantine bonds    adamantine chains

Vnleſſe the Deſtin's adamantine band / Should tye my teeth, I cannot chuſe but bite, […]

Synonym of adamant.

For two hours they stand; [François Claude Amour, marquis de] Bouillé's sword glittering in his hand, adamantine resolution clouding his brows; […]

He [William III of England] was proved by every test; […] by the imminent and constant risk of assassination, a risk which has shaken very strong nerves, a risk which severely tried even the adamantine fortitude of [Oliver] Cromwell.

Synonym of adamant.

I thought this last information would soften the young man, but he was adamantine. He informed me that it was against all bank rules for a woman to draw from her husband's deposit without his order.

Synonym of adamant.

Embravvne your ſoft-skind encloſure vvith Adamantine duſt, that it may dravve nothing but ſteele vnto it.

All mens eyes vvere preſently turnd to the North, ſtanding euen ſtone-ſtill in their Circles, like the poynts of ſo many Geometricall needles, through a fixed & Adamantine deſire to behold this 45. yeares vvonder novv brought forth by Tyme: […]

Synonym of adamantium (“a fictional metal which is indestructible or nearly so”).