What does ‘intersex’ mean?

Intersex people are born with sex characteristics (including genitals, gonads and chromosome patterns) that do not fit typical binary notions of male or female bodies. Intersex is an umbrella term used to describe a wide range of natural bodily variations. In some cases, intersex traits are visible at birth while in others, they are not apparent until puberty. Some chromosomal intersex variations may not be physically apparent at all.
Intersex Fact Sheet. United Nations Human Rights Office of the High Commissioner, 2016. PDF.

Intersex is the lived experience of the socio-cultural consequences of being born with a body that does not fit the normative social constructions of male and female.
-van der Have MJ, van Heesch MA (2016). Intersex, a post-medicine definition [PowerPoint Slides], presented at WPATH 2016, Amsterdam.