What is another word for under-structures?
Pronunciation: [ˌʌndəstɹˈʌkt͡ʃəz] (IPA) 
Under-structures are the supporting foundations that uphold a construction or edifice. Synonyms for under-structures include foundation, substructure, base, base support, footing, baseboard, cornerstone, and pilings. The foundation is the most fundamental synonym for under-structure and is often called the groundwork of a building. The substructure is the lower portion of a building, which includes the foundation. The term base support describes a group of structures that support the foundation of a building, such as beams or columns. Footing is a broad term that refers to any part of the substructure that supports the foundation. Baseboard is a more specific term that refers to the covering at the base of a structure or building. The cornerstone is the initial building block in the foundation that sets the structure's course. Finally, the pilings are long wooden or concrete columns driven deep into the ground to secure the foundation of a building.
