The quality or state of not being affected by age; the condition of being timeless or appearing to remain forever young or unchanged.
From 'ageless' (age + -less) plus the nominalization suffix '-ness' (from Old English 'nyss'). A modern formation emphasizing the abstract quality of timelessness.
There's something almost philosophical about the word 'agelessness'—it captures human desire to transcend time, which is why it appears so often in beauty advertising, poetry, and fantasy stories.
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