A number of species displayed sexual dimorphism between genders and social conditioning would further distinguish the males and females of the species. For example, in many mammalian and some reptilian species, the females were distinguished by breasts and a slighter build. This dimorphism was further distinguished in the Devaronian species, with the females possessing a coat of fur and no horns. Males of many species tended to be larger with a broader build. The sexes were further distinguished by the tendency for males to be more assertive and dominant in society. Exceptions to this social hierarchy were developed in the Hapes Cluster and on Dathomir where females were the more dominant sex.
Droids, especially those with complex personalities and those which worked in close partnerships with organic beings, such as protocol droids and astromech droids, were often programmed as having either masculine or feminine character.