Acre

1. n. A piece of land, containing 160 square rods, or 4,840 square yards, or 43,560 square feet. This is the English statute acre. That of the United States is the same. The Scotch acre was about 1.26 of the English, and the Irish 1.62 of the English.
2. n. Any field of arable or pasture land.

The word meanings were obtained from OPTED(The Online Plain Text English Dictionary), which is based on “The Project Gutenberg Etext of Webster’s Unabridged Dictionary” which is in turn based on the 1913 US Webster’s Unabridged Dictionary (See Project Gutenburg), as a text file.