The Collaborative International Dictionary of English v.0.48:

Littleness \Lit"tle*ness\, n.
   The state or quality of being little; as, littleness of size,
   thought, duration, power, etc.
   [1913 Webster]

   Syn: Smallness; slightness; inconsiderableness; narrowness;
        insignificance; meanness; penuriousness.
        [1913 Webster]

WordNet (r) 3.0 (2006):

littleness
    n 1: the property of having a relatively small size [syn:
         smallness, littleness] [ant: bigness, largeness]
    2: the property of having relatively little strength or vigor;
       "the smallness of her voice" [syn: smallness, littleness]
    3: lack of generosity in trifling matters [syn: pettiness,
       littleness, smallness]

Moby Thesaurus II by Grady Ward, 1.0:

130 Moby Thesaurus words for "littleness":
   abjectness, abominableness, atrociousness, authoritarianism,
   baseness, beggarliness, bigotry, blind side, blind spot, blinders,
   brevity, briefness, closed mind, compactness, compendiousness,
   conciseness, contemptibility, contemptibleness, cramped ideas,
   crumminess, curtness, daintiness, debasement, deficiency,
   degradation, delicacy, depravity, despicableness, diminutiveness,
   enormity, execrableness, exiguity, exiguousness, failure,
   fanaticism, fewness, foulness, fulsomeness, grossness, heinousness,
   hideboundness, illiberality, immateriality, imperfection,
   inadequacy, incompetence, inconsequence, inconsequentiality,
   inconsiderableness, indifference, ineffectuality, inferiority,
   insignificance, instantaneousness, insufficiency, insularism,
   insularity, irrelevance, little-mindedness, low priority, lowness,
   maladroitness, marginality, meagerness, mean mind, meanness,
   mediocrity, minginess, minuteness, miserableness, moderateness,
   monstrousness, narrow sympathies, narrow views, narrow-mindedness,
   narrowness, nearsightedness, nefariousness, negligibility,
   niggardliness, obnoxiousness, odiousness, odium theologicum,
   paltriness, parochialism, pettiness, petty mind, picayune,
   picayunishness, pokiness, poorness, provincialism, puniness,
   purblindness, rankness, scabbiness, scantiness, scrubbiness,
   scruffiness, scumminess, scurviness, secondariness, shabbiness,
   shoddiness, short time, shortness, shortsightedness, shut mind,
   slightness, smallness, squalor, stinginess, straitlacedness,
   stuffiness, subnormality, succinctness, summariness, tininess,
   transience, triviality, uncatholicity, ungenerousness,
   unimportance, unimpressiveness, unmagnanimousness,
   unnoteworthiness, unskillfulness, vileness, vulgarity,
   wretchedness