The Collaborative International Dictionary of English v.0.48:

Aspersion \As*per"sion\, n. [L. aspersio, fr. aspergere: cf. F.
   aspersion.]
   1. A sprinkling, as with water or dust, in a literal sense.
      [1913 Webster]

            Behold an immersion, not and aspersion. --Jer.
                                                  Taylor.
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   2. The spreading of calumniations reports or charges which
      tarnish reputation, like the bespattering of a body with
      foul water; calumny.
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            Every candid critic would be ashamed to cast
            wholesale aspersions on the entire body of
            professional teachers.                --Grote.
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            Who would by base aspersions blot thy virtue.
                                                  --Dryden.
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WordNet (r) 3.0 (2006):

aspersion
    n 1: a disparaging remark; "in the 19th century any reference to
         female sexuality was considered a vile aspersion"; "it is
         difficult for a woman to understand a man's sensitivity to
         any slur on his virility" [syn: aspersion, slur]
    2: an abusive attack on a person's character or good name [syn:
       aspersion, calumny, slander, defamation,
       denigration]
    3: the act of sprinkling water in baptism (rare) [syn:
       aspersion, sprinkling]