mutable Definition

mutable
adj

1. Subject to or able to change; variable.

Thesaurus: changing, vacillating, wavering, alterable, flexible, fickle, uncertain, doubtful, unstable, unsteady; Antonym: constant, invariable, permanent.

Derivative: mutability
noun

The quality or state of being mutable
Thesaurus: instability, variability, volatility, vacillation, irresolution, uncertainty.

Derivative: mutably
adverb

Etymology: 14c: from Latin mutabilis, from mutare to change.