Territory or domain; a physical or political area controlled or occupied by an entity.
その島は国の領域に含まれている。
That island is included within the country's territory.
生物学では生物の生息領域を調べることが重要だ。
In biology, studying organisms' habitats (territories) is important.
A field, area, or domain of activity or study; a sphere of expertise or responsibility.
人工知能は今や多くの学術領域に影響を与えている。
Artificial intelligence now influences many academic fields.
彼の専門領域は環境経済学だ。
His area of expertise is environmental economics.
この課題は私の領域外なので助けが必要だ。
This task is outside my area, so I need help.
In mathematics, a domain or region: a specified subset of the plane or space (e.g., planar region, domain of definition).
この関数は複素領域で解析的に定義されている。
This function is analytically defined on a complex domain.
問題文では平面領域D上の積分を求めよとある。
The problem asks to evaluate an integral over the planar region D.