Neutrois, agendered, or genderless is to the spectrum of gender as asexuality is to the spectrum of sexuality.
Just as asexuality is not celibacy, as asexuality denotes an absence of interest rather than a state of self-imposed abstinence (with which it is often confused, much to the frustration of ace people everywhere), genderlessness is not a state of having rejected the gender binary or the gender spectrum as a whole- it is an absence of a gender identity, of any gender identity, of the masculine, the feminine, of any combination therein, and of all that lies outside of that which can still be quantified as gender. (About which I have no idea, but I’m certain something, or rather, a multitude of somethings, exist nonetheless.)