Smallgender is a type of agender/gendervoid where one feels like they have half a gender and the other half is just nothing. It can also mean when someone is demigender/genderflux but doesn't know what gender it is. Having an overly fluid gender is also smallgender, because not always knowing your current gender counts as smallgender.
History
Smallgender was created when julia2002thewikiuser thought that "there should be a gender equivilant of smallsexual and smallromantic."