irreversible

If you can't undo something, it's irreversible. Time is always irreversible, as is the damage done to your skin by too much sun, so be sure to wear sunblock!

While you see reverse inside of this word, you wouldn't use it to describe a car that can't go backwards. However, if the car was in an accident and cannot be fixed, you could say that the damage done to the car was pretty much irreversible, in other words the car is totaled.

Definitions of irreversible
1

adj incapable of being reversed

irreversible momentum toward revolution”
Synonyms:
permanent
not capable of being reversed or returned to the original condition
Antonyms:
reversible
capable of reversing or being reversed
correctable
capable of being returned to the original condition; not necessarily permanent
rechargeable
capable of being recharged
show more antonyms...

Sign up, it's free!

Whether you're a student, an educator, or a lifelong learner, Vocabulary.com can put you on the path to systematic vocabulary improvement.