n. A form of masonry made of large stones loosely thrown together and then optionally grouted.
the GNU version of the Collaborative International Dictionary of English
n. Masonry constructed of unsquared stones that are irregular in size and shape.
The Century Dictionary and Cyclopedia
n. Masonwork built of rubble-stone.
Word Usage
"One of the major constructions at Alta Vista, the Labyrinth, is a sinuous walkway with pillars and turns, bordered by rubblework walls, and believed to have astronomical significance."