Superstructure

1. n. The sleepers, and fastenings, in distinction from the roadbed.
2. n. Any material structure or edifice built on something else; that which is raised on a foundation or basis
3. n. all that part of a building above the basement. Also used figuratively.

The word meanings were obtained from OPTED(The Online Plain Text English Dictionary), which is based on “The Project Gutenberg Etext of Webster’s Unabridged Dictionary” which is in turn based on the 1913 US Webster’s Unabridged Dictionary (See Project Gutenburg), as a text file.