1) Hold 2) Hold up 3) Support 4) Support from below 5) Support from beneath 6) Sustain 7) To corroborate 8) To furnish a foundation for 9) To give support to 
• (v. t.) To support by some solid foundation; to place something underneath for support. • (v. t.) To lay stones, masonry, etc., under, as the sills of a building, on which it is to rest.
[v] - support from beneath
To provide a new support under an existing structure without removal of the super structure.
to prop up or support from below; strengthen, as by reinforcing a foundation. · to replace or strengthen the foundation of (a building or the like). · to furnish a foundation for; corroborate: The author's conclusions are underpinned by references to experimental findings.