noun
1.
a totality of infinite time
in eternity there is no change or passing away
Synonyms: infinity, sempiternity
Related Word: endlessness, infiniteness, infinitude, perpetuity, timelessness
Contrasted words: ephemerality, impermanence, transience; limitedness, restrictedness
Antonyms: finiteness
2.
unending existence after death
belief in the eternity of our spiritual nature
Synonyms: afterlife, everlastingness, eviternity, immortality, world-without-end
3.
Synonyms: age 2, aeon, blue moon, coon's age, dog's age, donkey's years, long
Idioms: forever and a day, forever and ever