The Collaborative International Dictionary of English v.0.48:

Aerie \Ae"rie\ (?; 277), n. [OE. aire, eire, air, nest, also
   origin, descent, OF. aire, LL. area, aera, nest of a bird of
   prey, perh. fr. L. area an open space (for birds of prey like
   to build their nests on flat and open spaces on the top of
   high rocks). Cf. Area.]
   The nest of a bird of prey, as of an eagle or hawk; also a
   brood of such birds; eyrie. --Shak. Also fig.: A human
   residence or resting place perched like an eagle's nest.
   [1913 Webster]

WordNet (r) 3.0 (2006):

aerie
    n 1: the lofty nest of a bird of prey (such as a hawk or eagle)
         [syn: aerie, aery, eyrie, eyry]
    2: any habitation at a high altitude [syn: aerie, aery,
       eyrie, eyry]