public domain

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun Land owned and controlled by the state or federal government.
• noun The condition of not being protected by a patent or copyright and therefore being available to the public for use without charge.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun The realm of intellectual property being not protected under patent or copyright, i.e. no person or other legal entity can establish proprietary interests.
• noun Open land such as unowned prairie in the western and southwestern United States. Space not subject to a land patent.
• adjective this sense?) Not subject to any copyright or patent restrictions.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun property rights that are held by the public at large