“Innit” began as a shorter form of “isn’t it”, and at first it was presumably used in exactly the same way as its source. I don’t know when its usage diverged from “isn’t it”, but it now serves for other “tag questions” as well - it’s not only flexible in number and gender, but also able to stand for verbs other than be: “These have handles, innit”.
(I can’t tell if it works when the statement before the tag is negative. Does its usage permit “He can’t go out, innit”?)
It’s obviously nice to have a convenient all-purpose tag like that, that doesn’t require any grammatical markers. German (in general usage, not just informally) has more than one of them, including “nicht wahr?” (lit. “not true?”), which can follow just about any statement; I’m sure some other languages do too.
It also makes me wonder if there other words in English that are a contraction of a contraction. (I’m not sure if the originators of “innit” were qualified for that job - maybe they should have hired a contractor. )
Is the word too low-register and regional and new and unstable (and maybe ephemeral?) to have an entry or mention in etymonline?
I think “innit” is “high-register” enough to deserve it’s own entry. In my experience, people generally think of this word as it’s own thing, and that’s probably as good a standard as any for judging if a term should be treated.
I will say, the first example you shared does not sound right to my ear. I would need to be convinced that “innit” really is flexible enough to be used for plural cases.
I think if you found some early examples of the term in print, as well as examples showing the flexible usage you claim, that would be a good start toward having “innnit” added to Etymonline.
It’s a perfect sister to the French “N’est-ce pas?”. In fact, the ‘correct’ English equivalent tags: “Won’t she?”, “Aren’t they?”, “Isn’t it?”, Wouldn’t he?" “Shouldn’t you?” etc. present huge problems to non-English speakers.
I daresay that “innit?” (question mark duly included) belongs in the same semantic drawer as “ain’t”, “won’t”, “prolly”, “c’mon”, “shan’t”, and so many other verbal shortcuts that allow to save a syllable without affecting (much) the intelligibility of the sentence.
Severely frowned upon initially by purists, primary school teachers and spinster aunts, most of them nonetheless managed to elbow their way into the spoken language first and eventually into the dictionaries. So why should Etymonline snub a popular “innit?” while it hosts an “ain’t” that over 300 years of age make perfectly respectable?
Speaking of its function in the phrase, I think it extends slightly beyond that of a mere mouth filler or of a general purpose word: at least to my ears “innit?” – as well as its foreign brethren “nicht wahr?” / “oder?”, “n’est-ce pas?”, “¿verdad?”, “vero?” / “giusto?”, “prawda?” – implies a sort of rhetoric challenge to contradict the speaker. Try to reply “Naah, that’s all balderdash!” and you’ll have a fair chance to start a brawl
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Edit: OED does list “innit” (without question mark) and dates it to 1954 – not as old as “ain’t”, I’ll admit it, but still a respectable enough septuagenarian.
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