Ordinary birds have nests, but if you're a bird of prey you get a special moniker for the crib, and that word is aerie, also spelled aery, eyry, and eyrie. Birds with aeries typically build them very high, such as on clifftops, and aerie denotes more generally any very high nesting place or abode. The origins of the word aren't entirely clear but are probably from Latin. Acre may be a distant relative.