grillage definition by Webster's New World
Webster's New World College Dictionary Copyright © 2010 by Wiley Publishing, Inc., Cleveland, Ohio. Used by arrangement with John Wiley & Sons, Inc.
a framework of beams laid crosswise, used as a support or foundation, as for a building on soft ground
Origin: French wirework, grating, frame ; from grille: see grille
grillage definition by American Heritage Dictionary
A network or frame of timber or steel serving as a foundation, usually on ground that is wet or soft.
Origin: French, from Old French, trellis, from greille, gridiron; see grill.