Xynthvir is a singular gender identity, just like female, male, juxera, etc. It is a gender that, like proxvir, is derived but distinctly separate from manhood and masculinity. In the case of xynthvir, however, it is not just derived from masculinity; it is also derived from xeninity. Xynthvir is a single gender that is derived from both masculinity and xeninity, but is a single gender, not a mix of the two, and is still completely unrelated to how xenine individuals and masculine individuals experience their (respective) xeninity and masculinity.
Xynthvir is not a combination of masculine and xenine (xensculine), nor does it describe someone who is multigender who is both miaspec and xiaspec or has xenogenders. It is a distinctly separate gender from the two: derived from them but experienced as a singular, completely coalesced gender that relates heavily to qualities of masculinity described in an entirely non-standard xenine way. That experience is core to the gender but is still separate from "standard" masculinity and xeninity.
Since xynthvir is derived yet fully separate and distinct from masculinity and xeninity, xynthvir individuals may or may not identify as miaspec and/or xiaspec.
The feminine version of xynthvir is xynthera, the androgynous version of xynthvir is xynthari, and the outherine version of xynthvir is xynthouri.
The symbol for xynthvir individuals is the sun because, in nature and in many cultures, the sun is portrayed as being derived from masculine aspects and qualities, but it is still entirely separate from masculinity in a way that connects the gender experience to non-standard xeninity, making the sun the perfect symbol for xynthvir individuals.
The term xynthvir was coined by FANDOM user Reign of the breadsticcs (previously Reign of the queerios) on a blog post on March 11, 2021, along with its feminine and androgyne counterparts. They designed the flag the same day.
The first three flags were designed by FANDOM user Reign of the breadsticcs on March 11, 2021. The blue color scheme represents a combination of distinct masculinity and xeninity, with the black fade representing complete separation from "standard" xeninity and masculinity. The blue on the second flag represents masculinity, the orange represents xeninity, and the black represents the distinction between them and their "standard" forms.
The fourth flag was designed by FANDOM user Queerasstiefling on April 2, 2021. The orange represents the sun being a symbol for xynthvir individuals, the light green represents xeninity, and the blue represents masculinity.