Underbuilding n. : Same as Substruction.

Example:


Taxonomy
Rockville, Montgomery County Government, Map, County Government Center, Monroe Street, Parking Garage, Courthouse Square, Government Center, Parking Lot, Middle Lane, Maryland Avenue, Rockville Center, Rockville Pike, Rockville City Hall, Montgomery County, Maryland, Montgomery County, Maryland, Route 28.

Defination from the web:
... 8. Stella Werner Council Office Building. 100 Maryland Avenue (Use Parking Garage, see above) 9. 51 Monroe Street (Parking Under Building) 10. Rockville Center ...