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sexual dimorphism

noun

the condition in which the males and females in a species are morphologically different, as with many birds.

Origin of sexual dimorphism

First recorded in 1885–90
Related formssexually dimorphic, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for sexual dimorphism

sexual dimorphism

noun

biology differences in appearance between the males and females of a species
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
sexual dimorphism in Medicine

sexual dimorphism

n.

The physical differences between male and female individuals that arise as a consequence of sexual maturation, including the secondary sex characteristics.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.