A superstructure's an upward extension of an existing structure above a baseline. This term's applied both to physical structures like buildings, bridges or ships and to conceptual structures as well (for example, in social sciences). The word superstructure's a combination of the word super (Latin for above, in addition) with the word structure (also from Latin, meaning to build or to heap up). Engineering In order to improve seismic performance of buildings and bridges, a superstructure may b… (More on Superstructure)