Xenbinary means xenine/xenic binary. Someone who has binary gender(s) but leans xen(sex), is midbinary or endobinary, is xeno-aligned or just presents xeninely.
Xenbinary is different from xenogender, as xenic individuals are aligned with xenine things. It's up for personal interpretations. Xenbinary could also represent ambinary individuals.
History
The term was coined by tumblr user imoga-pride the 25th on August, 2020. The flag was made by tumblr user xenoleaf.