Tbf, there is a 'proper' definition after that, but I still think that it's extremely telling that the first line refers to the LGBT alphabet. As if that is the most important aspect - the sense of belonging.
"Intersex is an umbrella term for differences in sex traits or reproductive anatomy. Intersex people are born with these differences or develop them in childhood. There are many possible differences in genitalia, hormones, internal anatomy, or chromosomes, compared to the usual two ways that human bodies develop."
The last sentence is of course not correct either, and feeds into the 'sex is not binary' nonsense.