pi·las·ter (pĭ-lās'tər) n. A rectangular column with a capital and base, projecting only slightly from a wall as an ornamental motif.
[French pilastre, from Old French, from Old Italian pilastro, from Medieval Latin pīlaster : Latin pīla, pillar + Latin -aster, n. suff., or blend of Latin pīla, pillar, and Late Latin parastatēs, pilaster (from Greek, stay, supporter : para-, beside; see para-1 + -statēs, -stat).]
a square column, 1575, from M.Fr. pilastre (1545), from It. pilastro, from M.L. pilastrum (1341), from pila, "buttress, pile" (from L. pila, see pillar) + L. -aster, suffix expressing "incomplete resemblance."
Main Entry: pi·las·ter Pronunciation: pi-'las-t&r Function: noun : an elongated hardened ridge; especially: a longitudinalbony ridge on the back of the femur