What is the lowest and supporting part or member of a wall, including the base course (see Base course (a), under Base, n.) and footing courses; in a frame house, the whole substructure of masonry called?

foundation — (Arch.) The lowest and supporting part or member of a wall, including the base course (see Base course (a), under Base, n.) and footing courses; in a frame house, the whole substructure of masonry. (Webster's 1913.)

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