n. A small slab of stone consecrated and laid upon or let into the top of an altar which has not been consecrated, or which has no stone mensa: often used as a portable altar.n. A piece of oak wood about six inches square, having a cross on one side and the figure of a patron saint on the other. It was blessed and incased in gold or silver. It was, in the middle ages, covered with a purple pall during certain celebrations. z