
1) Ancient Roman architecture 2) Dinette, ancient style 3) Roman banquet room 4) Room or hall in ancient Rome
Found on
https://www.crosswordclues.com/clue/oecus

Oecus, the Latinized form of Gr. oikos, house, used by Vitruvius for the principal hall or salon in a Roman house, which was used occasionally as a triclinium for banquets. When of great size it became necessary to support its ceiling with columns; thus, according to Vitruvius, the tetrastyle oecus had four columns; in the Corinthian oecus there w...
Found on
http://en.wikipedia.org/wiki/Oecus

A type of living or reception room in the Roman house.
Found on
http://www.encyclo.co.uk/visitor-contributions.php
No exact match found.