Extersex is a term for those who do not know whether they are dyadic or intersex. It could be because one feels as though they might be some form of intersex, but are unable to medically confirm it, or cannot confirm what intersex variation it is. It may also be for those who have a variation that may be considered intersex, but are uncertain if they want to identify as intersex.
The term appears to have been coined by Tumblr user xenoqueer on or before August 24, 2018.
The extersex flag was created by ClownCar on September 16, 2021.
Exter- comes from the word 'external,' which references that one cannot tell the depth of their sex traits simply from the outside.