A block in the (approximate) shape of a cube(noun)
WordNet. Princeton University. 2010.
Use "square block" in a sentence
"Fitler Square was one of Philadelphia’s historic pocket-parks, a square block limned by privet hedge and wrought-iron fence, with tasteful wooden benches around a center fountain and newly refurbished brickwork underfoot."
"It is, as he said, beautifully situated, but it is not beautiful in itself, for it is a large square block of a house, whitewashed, but all stained and streaked with damp and bad weather."