We coined the honorific "Mix." (or "mix."[1]) just by adding a letter to the gender neutral "Mx." and it is pronounced the same way. The intent is to have a plural signifier that isn't "The (blank) System" and flows into linguistic conventions already in place for singlet-normative society. This isn't to reify singlet normativity or "professionalism", but rather to make the linguistic adjustment easier, and to acknowledge through how we self-refer that we are all — singlet, plural, and multiple — systems[2]. The word "mix" connotes a mixture, different elements working together to create something new with no element being prioritized over the other.
Personally, we don't like introducing ourselves as "The Moss System" or "The Moss Collective" as we don't want to sign things with the word "The" — it just doesn't feel right for us or for how we conceive of our plurality. We prefer having a "system" name that can be used in citations cleanly and operates similar to a conventional given name. Individual headmates can be referenced as "headmate name, system name" similar to the "first name, last name" convention popular in our culture (though it could just as easily be "system name, headmate name") with individual headmates opting for honorifics that affirm their genders, such as Mx., Mr., Ms. and Mrs., Xn.[3] while we affirm our collective identity when appropriate with Mix.
Anyone can use this honorific so long as they identify in some way as a "mix" which may or may not mean identifying within any strict definition of plurality. If you are a singlet and are drawn towards this term we encourage you to ask yourself why and what it means to you, and if the answer is not that you think it would be a good show of ally/accompliceship (it wouldn't be) and it still feels right to you, go ahead. You can capitalize the M or not capitalize it as you& see fit and we encourage experimentation. The only thing we feel strongly about is that people who are "anti-endogenic"/sysmedicalists are not welcome to the term.
notes
1. We opt for not capitalizing the "M" just like we don't capitalize our names as we seek to challenge those who refer to us, including ourselves, to be intentional about how we choose which is worthy of honor and how by looking to that which is overlooked we can be challenged to construct our futures more creatively. This isn't about dishonoring ourselves, but decentering the first-person on the creative and social plane. Of course, we owe inspiration for this choice from bell hooks of blessed memory and to the many others before us who've made this choice.
2. For more on our thoughts regarding using "systems" to qualify plurals/multiples as seperate from singlets, see Who is a System? Theory and Terminology.
3. We are using "Xn./xn" personally for our headmates who do not feel comfortable with any of the other options and prefer to be referred to in a way that affirms that no gendered signifier — binary or nonbinary as they may be — is appropriate to refer to them as xenogendered individuals. You can read more at the coining post here: link.