Fair use (U.S. trademark law)
WordNet
noun
(1) The conditions under which you can use material that is copyrighted by someone else without paying royalties
WiktionaryText
Noun
- : 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
- 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, http://www.copyright.gov/fls/fl102.html