square measure

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. A system of units used in measuring area.

GNU Webster's 1913

1. n. the measure of superficial area of surfaces in square units, as inches, feet, miles, etc.
2. adj. the measure of a superficies or surface which depends on the length and breadth taken conjointly. The units of square measure are squares whose sides are the linear measures; as, square inches, square feet, square meters, etc.

WordNet 3.0

1. n. a system of units used to measure areas