• Today's Word

Immutable

🔊 Listen to the word Immutable

ih-MYOO-tuh-bul

Definition

(adjective) Unchanging over time or unable to be changed; permanent and fixed.

Example

The Constitution’s basic principles were designed to be immutable, requiring extraordinary effort to amend.

Word Origin

Late Middle English: from Latin “immutabilis,” from “in-” (not) + “mutabilis” (changeable), from “mutare” meaning “to change.”

Fun Fact

Computer programmers prize immutable data structures that cannot be altered once created, making code more predictable and secure. Philosophers debate whether anything is truly immutable—even supposedly eternal truths shift with new understanding. The phrase “immutable laws of nature” once included ideas later overturned by quantum mechanics and relativity. Religious texts often describe divine attributes as immutable, emphasizing permanence amid worldly change. Ironically, our understanding of what counts as immutable itself changes over time. Blockchain technology achieves immutability through cryptographic methods, creating permanent records that theoretically cannot be altered—though “theoretically” always carries weight in discussions of absolute permanence.