There's a kind of charm to a classic malapropism like this.
an act or habit of misusing words ridiculously, especially by the confusion of words that are similar in sound.
Most people know that the word malapropism (or malaprop) comes from the character of Mrs Malaprop in Richard Brinsley Sheridan's play The Rivals. A synonym is Dogberryism, likewise from the character Dogberry in the Shakespeare play Much Ado About Nothing, although this alternative came later.
The word malapropos has actually been in use in English since at least 1630 according to the OED. It derives from the French phrase mal à propos meaning 'poorly placed'. (This is also where we get the word apropos.)
If you're interested in how the brain stores and accesses vocabulary (which I am) then malapropisms actually give an intriguing glimpse into what on earth might be going on up there. The fact that we sometimes choose the wrong word based on aural similarities, even if there's no relation in significance, would seem to suggest that we can access words that sound or look similar to the one we are searching for in the same way we can think of words in the same semantic field when we're struggling with tip-of-the-tongue syndrome (or lethologica if you want to be fancy).
Of course, not all malapropisms are an example of this, because many of them arise from words simply being misheard and then people assuming the most logical option from what they already know. A very common malaprop is the 'could of'/'should of'/'would of' error, which happens because people hear the contraction 'could've' and assume the second word in the phrase is 'of' rather than 'have'. For a certain kind of person (read: me) it's also like nails on a blackboard.
Getting back to worm hall... Not that I don't enjoy the unexpected visual of an elegant gallery bedecked with interesting and unusual worm specimens, but in this case I assume the intended term is in fact 'wormhole':
a theoretical passageway in space between a black hole and a white hole.