Word Origin & History
floorO.E. flor "floor," from P.Gmc. *floruz "floor" (cf. M.Du. vloer, O.N. flor "floor," M.H.G. vluor, Ger. Flur "field, meadow"), from PIE *plaros (cf. Welsh llawr "ground"), enlarged from *pele- "flat, to spread." The verbal sense of "puzzle, confound" is 1830, from notion of "knock down to the floor" (1640s).
Related: Floored; flooring. The figurative sense in legislative assemblies is first recorded 1774. Floor plan attested from 1867.