Existence within time but infinitely into the future; as opposed to eternity, understood as existing outside time(noun)
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Use "sempiternity" in a sentence
"Truculency, was sempiternity of impeccable lagoon!"
"While in some places at least Plato connected the necessary character of the Forms, including mathematical objects, to eternity, in Aristotle the connection is between necessity and sempiternity."
"Our present connotes changing time and sempiternity; God's present, abiding, unmoved, and immoveable, connotes eternity."