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
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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
The physical differences between male and female individuals that arise as a consequence of sexual maturation, including the secondary sex characteristics.
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