1.
Eternity is time without an end or a state of existence outside time, especially the state which some people believe they will pass into after they have died.
I have always found the thought of ~ terrifying.
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2.
If you say that a situation lasted for an ~, you mean that it seemed to last an extremely long time, usually because it was boring or unpleasant.
The war continued for an ~...
= age
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