fair use

Short definition from Wiktionary

Noun

1. 1
   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.
2. 2
   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: Use of another party's intellectual property that is protected by this doctrine.