Achiralgender is an eugender without an antigender or an ungender, or vice-versa due to an impossibility of the reverse form.[1][2] It's a gender that cannot possess a polar opposite.
Flag
The achiralgender flag was coined by a user going by Amnisty on November 17th, 2020. The gold represent the lone genders that achiralgender encompasses, the black represents the lack of an antigender, and the white represents multigenders that inheritely have no opposite, such as pangender, since pangender encompasses agender as well, making no opposite for it.