[1] : The Collaborative International Dictionary of English v.0.48

immutable \immu"table\, a. l. immutabilis; pref. im- not +
   mutabilis mutable. see mutable.
   not mutable; not capable or susceptible of change;
   unchangeable; unalterable.
   1913 webster

         that by two immutable things, in which it was
         impossible for god to lie, we might have a strong
         consolation.                             --heb. vi. 18.
   1913 webster

         immutable, immortal, infinite,
         eternal king.                            --milton.
   -- immu"tableness, n. -- immu"tably, adv.
   1913 webster
see also:
mutable immu"tableness immu"tably 

[2] : WordNet (r) 2.0

immutable
     adj : not subject or susceptible to change or variation in form or
           quality or nature; "the view of that time was that all
           species were immutable, created by god" syn: changeless
           ant: mutable
see also:
changeless mutable 

[3] : Moby Thesaurus II by Grady Ward, 1.0

256 moby thesaurus words for "immutable":
   abiding, accordant, adamant, adamantine, age-long, aged, alike,
   all-knowing, all-powerful, all-seeing, all-wise, almighty, ancient,
   antique, balanced, boundless, cast-iron, changeless, chronic,
   consistent, consonant, constant, continuing, continuous,
   correspondent, creating, creative, diligent, diuturnal, dogged,
   dour, durable, enduring, equable, equal, eternal,
   eternally the same, even, evergreen, everlasting, faithful, firm,
   fixed, flat, flinty, frozen, glorious, good, grim, hallowed, hard,
   hard-core, hardy, highest, holy, homogeneous, immobile, immortal,
   immovable, implacable, impliable, inalterable, incommutable,
   inconvertible, indefatigable, indefeasible, indomitable, inductile,
   industrious, inelastic, inert, inexorable, inextensible,
   inextensile, inextensional, infinite, inflexible, insistent,
   insusceptible of change, intact, intractable, intractile,
   intransient, intransigent, intransmutable, invariable, inveterate,
   invincible, inviolate, iron, irreconcilable, irresilient,
   irretrievable, irreversible, irrevocable, just, lasting, level,
   limitless, long-lasting, long-lived, long-standing, long-term,
   longeval, longevous, loving, loyal, luminous, macrobiotic,
   majestic, making, measured, mechanical, merciful, methodic,
   monolithic, never-tiring, noble, nonelastic, nonreturnable,
   nonreversible, nonstretchable, numinous, obstinate, of a piece,
   of long duration, of long standing, omnipotent, omnipresent,
   omniscient, one, ordered, orderly, patient, patient as job,
   perdurable, perduring, perennial, permanent, perpetual,
   perseverant, persevering, persistent, persisting, pertinacious,
   plodding, plugging, preoccupied, quiescent, radiant, rapt, regular,
   relentless, remaining, resolute, reverseless, rigid, rigorous,
   robotlike, rock-ribbed, sacred, sedulous, sempervirent, shaping,
   single-minded, sleepless, slogging, smooth, solid, sovereign,
   stable, static, stationary, staying, steadfast, steady, steely,
   stern, stiff, stubborn, supreme, sustained, systematic, tenacious,
   timeless, tireless, torpid, tough, ubiquitous, unabating,
   unaffected, unalterable, unalterative, unaltered, unbending,
   unbounded, unbroken, unchangeable, unchanged, unchanging,
   unchecked, uncompromising, unconquerable, undaunted, undefined,
   undeflectable, undestroyed, undeviating, undifferentiated,
   undiscouraged, undiversified, undrooping, unextendible,
   unextensible, unfading, unfailing, unfaltering, unflagging,
   unflexible, unflinching, ungiving, uniform, unintermitting,
   uninterrupted, unlimber, unlimited, unmalleable, unmodifiable,
   unmovable, unmoved, unnodding, unpliable, unpliant, unrelaxing,
   unrelenting, unremitting, unrestorable, unreturnable, unruffled,
   unshifting, unsleeping, unsusceptible, unswerving, untiring,
   untractable, unvariable, unvaried, unvarying, unwavering,
   unwearied, unwearying, unwinking, unyielding, utterly attentive,
   vital, weariless

[4] : Bouvier's Law Dictionary, Revised 6th Ed (1856)

immutable. what cannot be removed, what is unchangeable. the laws of god 
being perfect, are immutable, but no human law can be so considered. 

Immutable >> I Words
Immutable, definition of term: Immutable
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