a. The right to purchase something before others, especially the right to purchase public land that is granted to one who has settled on that land.
b. A purchase made by such a right.
2. Prior seizure of, appropriation of, or claim to something, such as property.
3. The action of preempting, as the use of military force in a preemptive attack.
4. Law The doctrine that federal law takes precedence over state law.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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