"open space, level or sloping, especially in front of a fortification," 1590s, from French esplanade (15c.), from Spanish esplanada "large level area," noun use of fem. past participle of esplanar "make level," from Latin explanare "make level, flatten," from ex "out" (see ex-) + planus "flat" (from PIE root *pele- (2) "flat; to spread"). Or perhaps the French word is from or influenced by Italian spianata, from spianare.
updated on October 13, 2017