timeless

adjective
1

Eternal.

2

Not affected by time; ageless.

3

Done at an improper time; unseasonable; untimely.

4

Not decreasing over time in quality and appeal.

"The cave carvings have a timeless beauty."

5

Without a time limit; untimed.

"a timeless cricket match"

6

Outside of time; extratemporal.

noun
1

A gene encoding an essential protein that regulates circadian rhythm, normally written in italics: timeless.

Source: https://en.wiktionary.org/wiki/timeless

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