eternal

adjective
1

Lasting forever; unending.

"One could say time is eternal."

2

Existing outside time; as opposed to sempiternal, existing within time but everlastingly.

3

Constant; perpetual; ceaseless; ever-present.

4

Exceedingly great or bad; used as an intensifier.

"some eternal villain"

noun
1

One who lives forever; an immortal.

Source: https://en.wiktionary.org/wiki/eternal

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