This word is acceptable for play in the US & UK dictionaries that are being used in the following games:

• Lexulous
• Wordscraper
• Wordosaur

adj. Capable of or subject to change or alteration.

adj. Prone to frequent change; inconstant: mutable weather patterns.

adj. Tending to undergo genetic mutation: a mutable organism; a mutable gene.

adj. Changeable; inclined to mutate.

adj. Having a value that is changeable during program execution.

adj. Capable of alteration; subject to change; changeable in form, qualities, or nature.

adj. Changeable; inconstant; unsettled; unstable; fickle.

Capable of being altered in form, qualities, or nature; subject to change; changeable.

Changeable or inconstant in mind or feelings; unsettled; unstable; liable to change.

Synonyms Alterable.

Unsteady, wavering, variable, irresolute, fickle, vacillating.

adj. capable of or tending to change in form or quality or nature

"Not always smoothly — Peirce himself parted ways with his fellow pragmatist William James, largely over the idea that truth was mutable, that is, what is "true" can become not true and even then true again, depending on the situation."

immutable   

alterable   

unsettled    inconstant    unstable    alterable    wavering    unsteady    variable    fickle    changeable   

disputable    immutable    indisputable    inscrutable    irrefutable    suitable    unsuitable   

perishable    destructible    inconstant    fallible    divisible    changeable    four-dimensional    transitory    unstable    dimensional