G0126–ἀΐδιος–aidios

-- for from [supplied: the] world's creation the invisible things of him are perceived, being apprehended by the mind through the things that are made, both his eternal power and divinity, -- so as to render them inexcusable.

ἀΐδιος aidios “eternal”

And angels who had not kept their own original state, but had abandoned their own dwelling, he keeps in eternal chains under gloomy darkness, to [supplied: the] judgment of [supplied: the] great day;

ἀϊδίοις aidiois “eternal”