floorplate

Short definition from Wiktionary

Noun

1. 1
   A (usually metal) plate used as industrial flooring.
2. 2
   A horizontal, structural, load-bearing member in platform framing (wooden building framing). Also called bottom plate, sill plate, sole plate or (lower) wall plate.
3. 3
   The structural base plate of the floors (storeys) of a building, usually made up of bottom panels, floor panels, floor slabs, paving slabs, hollow core slabs or beams or joists in timber constructions.
4. 4
   A specialized glial structure integral to the developing nervous system of vertebrate organisms.