1. The act or an instance of merging; union.
2. The union of two or more commercial interests or corporations.
3. Law. The absorption of a lesser estate, liability, right, action, or offense into a greater one.

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.