NOUN (1)

1. a person whose disease is incurable;


ADJECTIVE (2)

1. incapable of being cured;
- Example: "an incurable disease"
- Example: "an incurable addiction to smoking"

2. unalterable in disposition or habits;
- Example: "an incurable optimist"

The Collaborative International Dictionary of English v.0.48:

Incurable \In*cur"a*ble\, a. [F. incurable, L. incurabilis. See
   In- not, and Curable.]
   [1913 Webster]
   1. Not capable of being cured; beyond the power of skill or
      medicine to remedy; as, an incurable disease.
      [1913 Webster]

            A scirrhus is not absolutely incurable. --Arbuthnot.
      [1913 Webster]

   2. Not admitting or capable of remedy or correction;
      irremediable; remediless; as, incurable evils.
      [1913 Webster]

            Rancorous and incurable hostility.    --Burke.
      [1913 Webster]

            They were laboring under a profound, and, as it
            might have seemed, an almost incurable ignorance.
                                                  --Sir J.
                                                  Stephen.

   Syn: Irremediable; remediless; irrecoverable; irretrievable;
        irreparable; hopeless.
        [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Incurable \In*cur"a*ble\, n.
   A person diseased beyond cure.
   [1913 Webster]

WordNet (r) 3.0 (2006):

incurable
    adj 1: incapable of being cured; "an incurable disease"; "an
           incurable addiction to smoking" [ant: curable]
    2: unalterable in disposition or habits; "an incurable optimist"
    n 1: a person whose disease is incurable

Moby Thesaurus II by Grady Ward, 1.0:

53 Moby Thesaurus words for "incurable":
   apoplectic, arthritic, beyond recall, beyond remedy, case,
   consumptive, cureless, dyspeptic, epileptic, fatal, gone, habitual,
   hopeless, immedicable, impossible, incorrigible, inoperable,
   inpatient, invalid, inveterate, irreclaimable, irrecoverable,
   irredeemable, irreformable, irremediable, irreparable,
   irretrievable, irreversible, irrevocable, lost, outpatient,
   past hope, past praying for, patient, relentless, remediless,
   rheumatic, ruined, shut-in, sick person, spastic, sufferer,
   terminal, terminal case, the sick, uncorrectable, undone,
   unflagging, unmitigable, unrelievable, unsalvable, unsalvageable,
   valetudinarian