nymphæum

from The Century Dictionary.

• In classical antiquity:
• A sanctuary or shrine of the nymphs; a place sacred to a nymph.
• In ancient Roman villas, a room or gallery with niches and recesses for statues and plants, and often ornamented with columns, fountains, and other decorative features.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun Alternative spelling of nymphaeum.