noun
outermost bailey; third bailey
In Japanese castle architecture, the outermost defensive enclosure, outside the 二の丸 (second bailey) and 本丸 (inner bailey). A historical term; modern usage is mainly in historical descriptions or place names.
江戸城の三の丸には、現在、皇居東御苑が広がっている。
The East Gardens of the Imperial Palace now occupy the site of Edo Castle's outermost bailey.
三の丸は、城の最も外側の防御区域だった。
The third bailey was the outermost defensive area of the castle.