Blackacre, Whiteacre, Greenacre, Brownacre, and variations are the placeholder names used for fictitious estates in land.

The names are used by professors of law in common law jurisdictions, particularly in the area of real property and occasionally in contracts, to discuss the rights of various parties to a piece of land. A typical law school or bar exam question on real property might say:

Adam, owner of a fee simple in Blackacre, conveyed the property "to Bill for life, remainder to Charles, provided that if any person should consume alcohol on the property before the first born son of Charles turns twenty-one, then the property shall go to Dwight in fee simple." Assume that neither Bill, Charles, nor Dwight is an heir of Adam, and that Adam's only heir is his son, Edward. Discuss the ownership interests in Blackacre of Adam, Bill, Charles, Dwight and Edward.

Where more than one estate is needed to demonstrate a point  perhaps relating to a dispute over boundaries, easements or riparian rights  a second estate will usually be called Whiteacre,[1] a third, Greenacre, and a fourth, Brownacre.