Source : Webster's Revised Unabridged Dictionary (1913)

Antimacassar \An`ti*ma*cas"sar\, n.
   A cover for the back or arms of a chair or sofa, etc., to
   prevent them from being soiled by macassar or other oil from
   the hair.

Source : WordNet®

antimacassar
     n : a piece of ornamented cloth that protects the back of chair
         from hair oils