akropoleis

But the harmost and the Spartan garrison still retained their hold on their Akropoleis, or citadels, as a guarantee that Spartan interests should suffer no serious injury.

1877, Charles Sankey, The Spartan and Theban Supremacies, page 83

The sacred fire, emblem of common, patrilineal ancestry, was kept perpetually burning on the akropoleis of a thousand cities, focusing (“focus” was the Roman word for this flame) the loyalty of a still tribal people.

1983, William R. Everdell, The End of Kings: a history of republics and republicans, page 31

So the use of the word polis to designate an akropolis was probably restricted to akropoleis that were centres of human habitation. On the other hand, the akropoleis which were called poleis did not have to be the centres of a polis in the political sense of the term, as were e.g. the akropoleis of Athens or Korinth.

1996: Mogens Herman Hansen & Det Kongelige Danske Videnskabernes Selskab, Introduction to an Inventory of ‘poleis': Symposium August, 23–26, 1995, pp35–36