Inalterable

Part of speech: adjective

Definitions

1. Incapable of being changed or modified under any conditions
2. Fixed in nature and resistant to alteration or modification in every instance
3. Not subject to change or variation under any circumstances

Etymology: "Inalterable" is simply "alterable" with the negating prefix "in-" attached, so its meaning is built almost entirely from parts that were already in English. The prefix "in-" comes from Latin, where it could mean "not" or, in other contexts, "in" or "into"; English uses the negating sense in many words such as "inactive" and "incorrect." Attached to "alterable," it produces a word meaning "not able to be altered." The base word "alterable" rests on the verb "alter," which came into English from Latin "alterare," meaning "to make other," from "alter," "the other of two." That root gives "alter" its core sense of changing something into a different state, and "alterable" describes anything capable of undergoing such a change. Adding "in-" reverses the idea, so the adjective names something that resists or cannot undergo that change.

Synonyms: unchangeable, immutable, fixed, constant, permanent

Antonyms: changeable, alterable, variable, flexible, modifiable