a. [f. next + -AL.] Belonging to or constituting a superstructure.

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1884.  Traill, in Macm. Mag., Nov., 30/1. These are the actual limits of the argumentative foundation which has been made to bear so vast a superstructural conclusion.

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1893.  Home Missionary (N.Y.), July, 144. Foundational rather than superstructural.

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