The Collaborative International Dictionary of English v.0.48:

Abradant \Ab*ra"dant\, n.
   A material used for grinding, as emery, sand, powdered glass,
   etc.
   [1913 Webster]

WordNet (r) 3.0 (2006):

abradant
    n 1: a substance that abrades or wears down [syn: abrasive,
         abradant, abrasive material]
    2: a tool or machine used for wearing down or smoothing or
       polishing [syn: abrader, abradant]