Altengender is a xenogender that has a relation with shapes. For example, one might imagine their gender to be a particular shape.
Alten- can be added to any shape: altensquare, altenheart, etc.
History
This xenogender was coined by Reddit user u/hiitsyaz on June 16, 2021. The flag was designed around the same time by Instagram user mogai.terms.xenogenders.
Etymology
The name alten- comes from the German word ‘gestalten’ which means shape.