fair use
noun
Definitions
A doctrine in intellectual property law that permits one party to make use of another party's protected intellectual property (such as a copyright or trademark) under narrowly defined circumstances.
Example: Although fair use was not mentioned in the previous copyright law, the doctrine has developed through a substantial number of court decisions over the years. United States Copyright Office Statement on Fair Use, https//web.archive.org/web/20071220093741/http://www.copyright.gov/fls/fl102.html