Emily Dickinson Lexicon

MU-TA-BIL'I-TY, n. [Fr. mutabilité; It. mutibilità; L. mutabilitas, from mutabilis, muto, to change.]

1. Changeableness; susceptibility of change; the quality of being subject to change or alteration, either in form, state or essential qualities. Plato confesses that the heavens and the frame of the world are corporeal, and therefore subject to mutability. Stillingfleet.
2. The state of habitually or frequently changing.
3. Changeableness, as of mind, disposition or will; inconstancy; instability; as, the mutability of opinion or purpose.