Non-self-segregating morphology
The other day, while practising my Esperanto flashcards on Anki, I got a new word: bankalsono.
I didn’t recognise it, so I tried to parse it: bank'al'sono? Something about making a call to a bank? bankal'sono? A “Bankal sound”, whatever that might be?
Then I asked it to show me the answer: “Badehose” (swimming trunks).
Oh! It’s ban'kalsono!
Perhaps one should start using the apostrophes more often to separate the morphemes :)
Famous mis-segregations in German include Wach'stube vs. Wachs'tube; Blumento'pferde vs. Blumen'topf'erde; and be'in'halt'en vs. bein'halt'en. (Though in most cases, the alternate parse is merely humorous, or the entire pair might be a bit constructed.)