The Collaborative International Dictionary of English v.0.48:

Incorporeal \In`cor*po"re*al\, a. [Pref. in- not + corporeal:
   cf. L. incorporeus. Cf. Incorporal.]
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   1. Not corporeal; not having a material body or form; not
      consisting of matter; immaterial.
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            Thus incorporeal spirits to smaller forms
            Reduced their shapes immense.         --Milton.
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            Sense and perception must necessarily proceed from
            some incorporeal substance within us. --Bentley.
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   2. (Law) Existing only in contemplation of law; not capable
      of actual visible seizin or possession; not being an
      object of sense; intangible; -- opposed to corporeal.
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   Incorporeal hereditament. See under Hereditament.

   Syn: Immaterial; unsubstantial; bodiless; spiritual.
        [1913 Webster]

WordNet (r) 3.0 (2006):

incorporeal
    adj 1: without material form or substance; "an incorporeal
           spirit" [syn: incorporeal, immaterial] [ant:
           corporeal, material]