aa: a kind of lava; Hawaiian
laager, kraal, aasvogel: Afrikaans
radii, etc.
torii: a Japanese temple gate (?)
continuum, duumvirate

We can ignore the somewhat artificial classical words like euoi and Aiaiai. They hardly count as English.

In English see + er becomes seer, but in Dutch the comparable compounds do keep three eee's.

There's a town in Tahiti called Faaa.

In Finnish, y is a vowel pure and simple: and by combining haa 'wedding', 'night', and aie 'intention' you can make haayöaie. (I'm doing that from memory, and the first word might be wrong, but if so it's something equally applicable like hää.)

Shifting to consonants, in German Ballett + tanzer formerly gave Ballettanzer; the new system I believe renders this more logically as Balletttanzer. In English we're deprived of this sight by the hyphens in gill-less and Inverness-shire.