(adj) capable of or tending to change in form or quality or nature, Syn. changeable, Ant. immutable, Example:a mutable substance; the mutable ways of fortune; mutable weather patterns; a mutable foreign policy
The Collaborative International Dictionary of English (GCIDE) v.0.53 Collaborative International Dictionary (GCIDE)
a. [ L. mutabilis, fr. mutare to change. See Move. ] 1. Capable of alteration; subject to change; changeable in form, qualities, or nature. [ 1913 Webster ]
Things of the most accidental and mutable nature. South. [ 1913 Webster ]
[そら, sora] (n) (1) empty air; sky; (2) { Buddh } shunya (emptiness, the lack of an immutable intrinsic nature within any phemomenon); (3) (abbr) (See 空軍) air force; (n, adj-na) (4) fruitlessness; meaninglessness; (5) (See 五大・1) void (one of the five elements)#1345
[ふえきりゅうこう, fuekiryuukou] (exp) the principle of fluidity and immutability in haiku; Haiku is both "fluid and transitory" and "eternal and immutable."; An interchange between the transient and the immutable is central to the soul of haiku. (Basho)