The Collaborative International Dictionary of English v.0.48:

Tangible \Tan"gi*ble\, a. [L. tangibilis, fr. tangere to touch:
   cf. F. tangible. See Tangent.]
   1. Perceptible to the touch; tactile; palpable. --Bacon.
      [1913 Webster]

   2. Capable of being possessed or realized; readily
      apprehensible by the mind; real; substantial; evident. "A
      tangible blunder." --Byron.
      [1913 Webster]

            Direct and tangible benefit to ourselves and others.
                                                  --Southey.
      [1913 Webster] -- Tan"gi*ble*ness, n. -- Tan"gi*bly,
      adv.
      [1913 Webster]

WordNet (r) 3.0 (2006):

tangible
    adj 1: perceptible by the senses especially the sense of touch;
           "skin with a tangible roughness" [syn: tangible,
           touchable] [ant: impalpable, intangible]
    2: capable of being treated as fact; "tangible evidence"; "his
       brief time as Prime Minister brought few real benefits to the
       poor" [syn: real, tangible]
    3: (of especially business assets) having physical substance and
       intrinsic monetary value ; "tangible property like real
       estate"; "tangible assets such as machinery" [ant:
       intangible]
    4: capable of being perceived; especially capable of being
       handled or touched or felt; "a barely palpable dust"; "felt
       sudden anger in a palpable wave"; "the air was warm and close
       --palpable as cotton"; "a palpable lie" [syn: palpable,
       tangible] [ant: impalpable]

Moby Thesaurus II by Grady Ward, 1.0:

81 Moby Thesaurus words for "tangible":
   actual, apparent, appreciable, assessed valuation, assets,
   assets and liabilities, atoms, bodily, circumstances, clear,
   clear as crystal, concrete, corporeal, crystal-clear,
   current assets, deferred assets, detectable, discernible, distinct,
   embodied, evident, explicit, express, fabric, fixed assets,
   frozen assets, funds, gross, indisputable, indubitable,
   intangible assets, intangibles, liquid assets, manifest, material,
   material assets, matter, means, medium, net assets, net worth,
   noticeable, objective, observable, obvious, open-and-shut,
   ostensive, palpable, patent, perceivable, perceptible, perspicuous,
   phenomenal, physical, plain, plain as day, ponderable,
   quick assets, real, resources, seeable, self-evident,
   self-explaining, self-explanatory, sensible, solid, somatic, stock,
   stock-in-trade, stuff, substance, substantial, substantive,
   tactile, tangible assets, tangibles, to be seen, touchable,
   unmistakable, visible, wealth