The concept that there exist alternate worlds or universes to the one in which we live.(noun)
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Use "alternity" in a sentence
"The full force of Steiner's image is in language as man's response to the "alternity" of evolution."
"Britain build "narratives of dislocation and alternity" with discursive responses transcending the conceptual category of nationalism and single national identities"
"This story of alternity identifies the smoke and mirrors itself as a heuristic; it is the visible which reveals the hidden."