Adultgender is a neurogender or xenogender specific for systems that have adults/bigs. It is a gender that can only be described by adults/bigs, since the experience of being an adult in a system is so unique the gender experiences that come with it would be just as unique as the adults themselves.
It can be used as a modifier or alongside other genders to help describe an adult's experience with gender, such as adultgirl, adultboy, adultenby, etc.
History
This term was coined by Cryptocrew, specifically Anderson, on June 4th - June 5th to describe his experiences. This term was coined through this page, and has no outside resources.