The word "enby" was first proposed on September 10, 2013 (the info was preserved for us by Gender Census) by a Tumblr user Vector (@/revolutionator), who was a nonbinary person using they/them pronouns. The original coining post text went as follows:
i wish there was an nb equivalent to words like boys and girls
nb
enby
enbies
The post is still available to view on Tumblr and has a little over 1k notes.
According to the blog post by Gender Census and also a tag left on the original post by a more recent reblogger, the word actually started circulating only after someone else made a post about it, which may have been this post from approximately November 1st of the same year that also introduces the term "enbyfriend".
Unlike what the post by Gender Census suggests, and what common present day understanding of "enby" suggests, I am not actually convinced that it was intended for use by children or teens only. I do not know how old Vector was at the time of coining the word, but in 2014 they were running an online resale shop in a different country. I was able to find some examples of definitions of the word "enby" from early into its existence, and these definitions equate it to just another way of saying "nonbinary":
from "NB", which stands for non-binary. These people do not identify with the male or female genders, and usually prefer "they" as a pronoun. They are neither men nor women, and should not be regarded as such.
Enbies can be genderqueer, agender, pangender, or any gender identity that is not binary.
enby=nonbinary person
it's the vocalization of "n-b", and is used in the place of "boy" or "girl" (alternatively, "man" or "woman"). so instead of saying "i'm a nonbinary person" i can say "i'm an enby". also it lets my gf use the term "enbyfriend" instead of "boyfriend" or "girlfriend".
not all nonbinary people like or use the term but it's one i like!
I found the word Enby (which is from the words non-binary, and are the equivalent of boy/girl), which I think is not only a cute word, but also very useful. Enby, or non-binary people are basically those that do not fit into the constructs we have of “boy/man” and “girl/woman”.
Enby is just a word that “N.B.” sounds like when said out loud. A lot of Non Binary people use it instead of “girl” or “boy” since “non binary person” is kind of a mouthful.
Nb or "enby" is short for "non-binary", and is an inclusive term for any genders that do not fall within the male/female gender binary.
I was also able to find some examples of people mentioning being an enby in posts related to jobs and other things that may indicate adult age. I will not cite all these posts, obviously, but I accessed them by searching up "enby before:2015-01-01", which gave me a sample of this word's use in the first year of its existence, and you can go check them out too.
My theory is that "enby" was not coined with a specific age range in mind, and "boys and girls" in the original post are simply used colloquially, just like "boyfriend", "fangirl", "femboy", or "catgirl" do not indicate age, but a degree of casualness.
That is, of course, just my view of the situation, and we can't know for sure what exactly Vector intended it as.
Someone did interpret "enby" as having to do with age back then too, though, since the coining post of "enban" dates back to January 21, 2014:
Okay everyone I want your input on this
We’re trying to make a mature version of “enby”, the equivalent of man/woman rather than enby’s equivalent of girl/boy.
I would like you to weigh in on this, lets make up a word.
Somebody has already suggested that “natio” is the latin word for people, so we could go with “natier” or “natie” or something like that.
Alternatively, we could slap an “an” on enby to get “enban” or something similar
Thoughts?
However, the word "enban" was then picked up by another big blog and removed from the age context again:
Enby/Enban - a noun form of “nonbinary” to be used similarly to “girl” or “boy”
Someone else in 2014 used that resource and ended up choosing "enban" over "enby" in a manner that did not seem like having anything to do with age. But the word "enban" did not catch on back then.
Something else of note to mention here is the first instance of use of the word "enbyphobia" I could find, dating November 28, 2013 - just a month and a half later than the word "enby" appeared.
I will probably cover some other derivative terms, as well as write something about later history of "enban", in a further post. For now, this concludes the section about origins of the word "enby".