The Collaborative International Dictionary of English v.0.48:

Sweetness \Sweet"ness\, n. [AS. sw[=e]tness.]
   The quality or state of being sweet (in any sense of the
   adjective); gratefulness to the taste or to the smell;
   agreeableness.
   [1913 Webster]

WordNet (r) 3.0 (2006):

sweetness
    n 1: the taste experience when sugar dissolves in the mouth
         [syn: sweet, sweetness, sugariness]
    2: the property of tasting as if it contains sugar [syn:
       sweetness, sweet]
    3: a pleasingly sweet olfactory property [syn: bouquet,
       fragrance, fragrancy, redolence, sweetness]
    4: the quality of giving pleasure; "he was charmed by the
       sweetness of her manner"; "the pleasantness of a cool breeze
       on a hot summer day" [syn: pleasantness, sweetness] [ant:
       unpleasantness]