The Collaborative International Dictionary of English v.0.48:

Materiality \Ma*te`ri*al"i*ty\, n. [Cf. F. mat['e]rialit['e].]
   [1913 Webster]
   1. The quality or state of being material; material
      existence; corporeity.
      [1913 Webster]

   2. Importance; as, the materiality of facts.
      [1913 Webster]

WordNet (r) 3.0 (2006):

materiality
    n 1: relevance requiring careful consideration [ant:
         immateriality]
    2: the quality of being physical; consisting of matter [syn:
       materiality, physicalness, corporeality, corporality]
       [ant: immateriality, incorporeality]

Moby Thesaurus II by Grady Ward, 1.0:

103 Moby Thesaurus words for "materiality":
   accent, air, applicability, application, appositeness, atom,
   atomic particles, bearing, being, body, brute matter,
   building block, chemical element, component, concern, concernment,
   concreteness, connection, consequence, consequentiality,
   consideration, constituent, density, durability, earth, element,
   elementary particle, elementary unit, emphasis, ens, entity, esse,
   essence, excellence, existence, fire, firmness,
   fundamental particle, germaneness, high order, high rank, hyle,
   hypostasis, import, importance, interest, life, mark, mass,
   material, material world, matter, merit, molecule, moment, monad,
   natural world, nature, note, occurrence, palpability, paramountcy,
   pertinence, physical world, plenum, ponderability, precedence,
   preeminence, presence, primacy, priority, reality, reference,
   regard, relatedness, relevance, respect, self-importance,
   significance, solidity, soundness, stability, steadiness,
   stoutness, strength, stress, stuff, sturdiness, subsistence,
   substance, substantiality, substantialness, substratum,
   superiority, supremacy, tangibility, the four elements, toughness,
   unit of being, value, water, weight, worth



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

MATERIALITY. That which is important; that which is not merely of form but
of substance.
     2. When a bill for discovery has been filed, for example, the defendant
must answer every material fact which is charged in the bill, and the test
in these cases seems to be that when, if the defendant should answer in the
affirmative, his answer would be of use to the plaintiff, the answer would
be material, and it must be made. 4 Price, R. 364; 13 Price, R. 291; 2 Y. &
J. 385.
     3. In order to convict a witness of a perjury, it is requisite to prove
that the matter he swore to was material to the question then depending.
Vide 3 Chit. Pr. 233; 3 Dowl. 104; 10 Bing. 340; Perjury.