1. The breeding of distantly related or unrelated individuals, often producing a hybrid of superior quality.
2. Anthropology. The mating of persons from different groups, often as a consequence of proscriptions against marriage within the group.

The American Heritage® Dictionary of the English Language, Fourth Edition Copyright © 2007, 2000 by Houghton Mifflin Company. Updated in 2009. Published by Houghton Mifflin Company. All rights reserved.