1) Aerial 2) Aeriform 3) Airy 4) Celestial 5) Choir voices 6) Cliff house 7) Ethereal 8) Ethereal, to poets 9) Habitation at a high altitude 10) High nest 11) High-altitude habitation 12) High-perched home 13) House of height 14) Insubstantial 15) Lofty loft 16) Lofty nest 17) Lofty nest, var 18) Pneumatic Found on https://www.crosswordclues.com/clue/aery