Several decades ago, I was briefly involved with a theatre in west London that had been built in the round. The theatre chairman delighted in referring to the access ways for actors in passages under the seating as the vomitoria, to the confusion and mild disgust of some patrons.
The disgust might merely have been due to the form of the word, but there has also long been an erroneous belief about the purpose of a Roman vomitorium. A classic example appeared in a totally forgotten American publication for children, Evening Round-Up by Col William C Hunter, dated 1915:
The residents of Pompeii had fine plumbing, baths and luxuries. They had a place called a vomitorium. The old Roman sports were gluttons; they stuffed themselves, then went to the vomitorium and threw up so they could eat more.
Though Romans did reputedly deliberately vomit so they could eat more of fine foods, they didn’t have a dedicated place in which to do it, and where they did do it was never called a vomitorium. The word was applied instead to the access ways in Roman theatres or amphitheatres that got the audience to and from their seats. H Rider Haggard, who had earlier written King Solomon’s Mines and She, got it right in his book Pearl-Maiden of 1901, about the fall of Jerusalem:
Beyond lay the broad passage of the vomitorium. They gained it, and in an instant were mixed with the thousands who sought to escape the panic.
There’s some excuse for the error. Latin vomitorium also referred to an emetic and vomere meant to vomit (and indeed is the source of our English word, via French); the figurative idea of an audience suddenly and violently issuing forth at the end of a performance gave rise to its application to an exit.
Having said all that, it turns out that there’s some doubt how often the word was actually used during the Roman period: I’m told it’s rare in Latin literature and the sense doesn’t even appear in some Latin dictionaries.
The theatre world, at least that part of it which works in the round, continues to keep the word alive in a sense that Romans would have understood, though — pace my youthful encounter — it does seem to be used more for access ways for actors than for members of the public.