What is to lay (a figure) upon another in such a manner that all the parts of the one coincide with the parts of the other; as, to superpose one plane figure on another called?

superpose — (Geom.) To lay (a figure) upon another in such a manner that all the parts of the one coincide with the parts of the other; as, to superpose one plane figure on another. (Webster's 1913.)

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