A system of genes in which two alleles are maintained in stable equilibrium because the heterozygote is more fit than either of the homozygotes.
Rise and Shine: 9 Sunny WordsRead more in this article about some frequently asked questions and fun facts related to our definitions.
Words And Phrases Your Parents Used That You Can’t Use NowParenting has changed over the years and so has the language. While some phrases were popular years ago, today they are obsolete ... and for good reason. Here are ten old expressions that your parents might have used but you wouldn't dare use today.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.