Obligender (pronounced ob-li-gender) is a gender that is defined by having a partial connection to one's AGAB because of coercion or abuse, as well as the presence of gender uncertainty. They feel obligated to performativity of their AGAB due to coercion/abuse, so they feel that their gender identity would be different had they not been through that, but because they have, their gender identity is different.
For example, an obligender person who is AFAB may feel that, due to abuse, their gender is still female because of their AGAB and coercion, but they aren't actually sure or certain about their gender identity and might not be female at all were it not for that coercion/abuse.
Obligender can be combined with terms to make it easier to specify one's gender experience, like oblimasculine, oblifeminine, etc.
Many cisn't individuals may feel "obligated" to be/perform their AGAB, but this term is specifically for those who feel that experience comes from coercion and abuse, so this term is exclusive to abuse victims.
History
Obligender was coined by tumblr user bazer63 some time before October 13, 2016, with the flag being designed by tumblr user to-reach-the-farthest-star, though both blogs and resources have since been deleted.
Note
The coiner of the term gave a disclaimer about it, saying that "I should make it known right now before all the “anti special snowflake” assholes come out of the woodwork, that I, the one who originally saw the need for this term, am a trauma victim who believes that this term will help other trauma victims who are trying to make sense of how their abuse and their gender identity intersect. Specifically, I am a CAFAB demigirl who feels like I would be fully agender if it weren’t for my past religious abuse. Please be considerate of that".