Is there an adjective meaning that an idea or object has longevity, or will still be relevant in the future?

(I believe I've heard such a word, but I can't think of it at the moment.)

Usage example:

While this textbook is interesting, it does not seem particularly [?]; five years from now, it will be useless.


6 Answers 6


There are a number of possible synonyms:

eternal, lasting, permanent, enduring, abiding, immortal, everlasting, ceaseless, immutable, indestructible, undying, ageless, imperishable, changeless.

The word required in your example, however, might be definitive, which carries the sense of being authoritative.

  • 2
    Another synonym: "transcendent". - Even "poetic" might be of service here. Context: I remember seeing someone's remarks once about people writing interesting, useful books, which will be widely read, but which won't outweigh so much as the idle sigh of a true poet. (Can anyone pin down this quote? - a casual googling didn't bring it to light.) Apr 5, 2012 at 8:15

Two additional ideas would be:

  • timeless ("not affected by time; ageless")
  • future-proof ("designed not to be obsolete in the future")

I like enduring; 'twas the first word that entered my mind.

Barrie listed many good candidates, but I'd like to add one more: persistent.

persistent |pərˈsistənt| (adj)
1. continuing firmly or obstinately in a course of action in spite of difficulty or opposition
2. continuing to exist or endure over a prolonged period


The word would be longevous, but this is archaic.

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    Dec 7, 2015 at 3:16

One good word is durable.

Merriam-Webster's definition:

able to exist for a long time without significant deterioration.


I was looking for a word like that too, and finally figured out that the word I was trying to think of was long-standing.

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