Sorry, probably not very standard terminology. I somehow picked it up from the OReilly book: Fonts & Encodings: From Advanced Typography to Unicode and Everything in Between

Page 55:

""" there are characters with no glyphs. glyphs that can correspond to a number of different characters according to context. Glyphs that correspond to multiple characters at the same time (with weightings assigned to each), and even more possibilities.

The problem of glyphs and characters is so complex that it has gone beyond the realm of computer specialists and has come to be of interest even to philosophers. For example, the Japanese philosopher Shigeki Moro, who has worked with ideographic characters in Buddhist documents, goes so far in his article Surface or Essence: Beyond Character Model Set [274] as to say that Unicode's approach is Aristotelian essentialist and to recommend supplanting it by an approach inspired by Jacques Derrida's theory of writing [114, 115]. The reader interested in the philosophical aspects of the issue is invited to consult [165,156], in addition to the works cited above. """

I think "essentialist" is probably a good description of the philosophy of how Unicode defines characters as opposed to fonts and glyphs, so I adopted it.

Well, Unicode didn't unify 門/门 either, but the appearance of the second glyph changes a lot depending on whether you use a Chinese font or a Japanese one. Meanwhile they did unify all the graphical variants of Latin characters with identical semantics, it's just that everyone is so used to the result that you hardly notice not being able to control whether g has a hook or a looped tail, and nobody expects to copy some German blackletter text into a French document and have it show up visually distinct, without explicitly setting the font.

Unicode has done the same unification for cuneiform languages. If you’re dealing with texts in Hittite, Sumerian, or Akkadian, you need to make sure you’re using the right fonts, otherwise the text will look entirely wrong.

Same thing, different code points is the opposite of han unification. Han unification is same code point, different thing.

Unicode merges some Chinese and Japanese characters into same code points and leave others as they are, on random per-character basis. So Chinese guys gets a ton of Japanese mixed texts and it causes tons of problems.

Japanese users are angry when system chooses Chinese fonts over Japanese, Chinese users apparently suffer with a font mishmash of Chinese and Japanese all the time like a mid-word capitalization. The official sanctioned solution is to just commit a genocide and nuke the offending language out of the system or to attach IVS to every Japanese characters which is like zero padding every single characters by a byte or two.

It's really putting everyone in pain and making absolutely no one happy, which sounds like what a good compromise tends to be, but LLMs seem to be struggling with there being multiple completely separate language families sharing codepoints but not character shapes or syntax. I've seen a smaller LLM model use made up verbs spilling over from the other language. I believe ML guys don't like datasets that do that kind of things. Same apply to image models.

We also have at least 15 copies of Latin alphabet in Unicode, all differently styled/fonted (there is chancery cursive, mathematical cursive, the fraktur version, the full-width version, etc.)