The Collaborative International Dictionary of English v.0.48:

Wholeness \Whole"ness\, n.
   The quality or state of being whole, entire, or sound;
   entireness; totality; completeness.
   [1913 Webster]

WordNet (r) 3.0 (2006):

wholeness
    n 1: an undivided or unbroken completeness or totality with
         nothing wanting; "the integrity of the nervous system is
         required for normal development"; "he took measures to
         insure the territorial unity of Croatia" [syn: integrity,
         unity, wholeness]
    2: a state of robust good health [syn: wholeness, haleness]

Moby Thesaurus II by Grady Ward, 1.0:

103 Moby Thesaurus words for "wholeness":
   advantageousness, agreeableness, allness, auspiciousness,
   beneficialness, benevolence, benignity, class, cogency,
   combination, completeness, comprehensiveness, desert,
   differentiation, differentness, distinctiveness, egohood,
   entireness, entirety, excellence, exhaustiveness, expedience,
   fairness, favorableness, fineness, first-rateness, fullness,
   fusion, goodliness, goodness, grace, haleness, healthiness,
   heartiness, helpfulness, holism, human factor, identity,
   inclusiveness, individualism, individuality, indivisibility,
   intactness, integrality, integration, integrity, inviolability,
   irreducibility, kindness, merit, niceness, nominalism,
   nonconformity, omnipresence, oneness, organic unity, particularism,
   particularity, perfection, personal equation, personal identity,
   personality, personship, pervasiveness, pleasantness, plenitude,
   profitableness, purity, quality, rewardingness, robustness,
   self-identity, selfhood, selfness, selfsameness, simplicity,
   singleness, singularity, skillfulness, solidarity, solidification,
   solidity, soul, soundness, superiority, thoroughness,
   total approach, totality, ubiquity, undividedness, unification,
   uniformity, uniqueness, unity, universality, univocity, usefulness,
   validity, value, vigor, virtue, virtuousness, worth