expanse (of something) a wide and open area of something, especially land or water a wide/vast expanse of blue sky flat expanses of open farmland Word Origin mid 17th cent.: from modern Latin expansum
‘something expanded’, neuter past participle of expandere ‘to spread out’, from ex- ‘out’ + pandere ‘to spread’.Extra examples She stood looking out over the flat expanse of fields. a bleak expanse of concrete a vast expanse of sand the desk’s shining expanse of polished wood the white expanses of the frozen north Above them was a vast expanse of blue sky. He gazed out over the huge expanses of open prairie. She admired the deck’s shining expanse of polished wood.