Ternabinary, Trinabinary, Trinary Abinary, or Ternary Abinary describes someone who is abinary but is not atrinary. A ternabinary individual experiences a single gender (monogender), that is not a xenogender (anthrogender), is not fluid or fluctuating (suptilian), and is often described as neutral or neuter. Ternabinary can also encompass genderlessness. Ternabinary is not necessarily a gender on it own (though it can be if desired), but is a category that encompasses many abinary genders such as neutrois, stellarian, agender, etc. It can be considered the subsequent category after "binary man" and "binary woman". It is sometimes occasionally called aliagender, third-gender, or "tertiary monogender".
The term and flag appear to have been created on the Tumblr blog beyond-mogai-pride-flags with help from gender-resource on December 24, 2020. The flag has no known meaning.