antependium

from The Collaborative International Dictionary of English v.0.48

Antependium \An`te*pen"di*um\, n. [LL., fr. L. ante + pendere to
   hang.] (Eccl.)
   The hangings or screen in front of the altar; an altar cloth;
   the frontal. --Smollett.
   [1913 Webster] Antepenult