Webster's Revised Unabridged Dictionary · 1913

Mutable

Mutable , adjective

[Latin mutabilis, from mutare to change. See Move.]

1.
Capable of alteration; subject to change; changeable in form, qualities, or nature.
Things of the most accidental and mutable nature. — South
2.
Changeable; inconstant; unsettled; unstable; fickle.
Most mutable wishes. — Byron