Gender includes the social, psychological, cultural and behavioral aspects of being a man, woman, or other gender identity.[1][2] Depending on the context, this may include sex-based social structures (i.e. gender roles) and gender expression.[3][4][5] Most cultures use a gender binary, in which gender is divided into two categories, and people are considered part of one or the other (boys/men and girls/women);[6][7][8] those who are outside these groups may fall under the umbrella term non-binary. Some societies have specific genders besides "man" and "woman", such as the hijras of South Asia; these are often referred to as third genders (and fourth genders, etc.). Most scholars agree that gender is a central characteristic for social organization.[9]
The social sciences have a branch devoted to gender studies. Other sciences, such as psychology, sociology, sexology and neuroscience, are interested in the subject. The social sciences sometimes approach gender as a social construct, and gender studies particularly do, while research in the natural sciences investigates whether biological differences in females and males influence the development of gender in humans; both inform the debate about how far biological differences influence the formation of gender identity and gendered behavior. Biopsychosocial approaches to gender include biological, psychological, and social/cultural aspects.[18][19]
^National Academies of Sciences, Engineering, and Medicine (2022). Bates, Nancy; Chin, Marshall; Becker, Tara (eds.). Measuring Sex, Gender Identity, and Sexual Orientation. Washington, DC: The National Academies Press. doi:10.17226/26424. ISBN978-0-309-27510-1. PMID35286054. S2CID247432505.{{cite book}}: CS1 maint: multiple names: authors list (link)
^Kevin L. Nadal, The Sage Encyclopedia of Psychology and Gender (2017, ISBN1483384276), p. 401: "Most cultures currently construct their societies based on the understanding of gender binary—the two gender categorizations (male and female). Such societies divide their population based on biological sex assigned to individuals at birth to begin the process of gender socialization."
^O'Halloran, Kerry (2020). Sexual orientation, gender identity and international human rights law: common law perspectives. London. pp. 22–28, 328–329. ISBN978-0-429-44265-0. OCLC1110674742.{{cite book}}: CS1 maint: location missing publisher (link)