Territory (noun)

1. A geographical area, typically one with defined political boundaries.
2. A region or area of control, influence, or ownership.
3. An area of the animal kingdom, especially that occupied by a particular species or group of species.
4. An area within a particular sphere of activity or interest.

Origin:

Mid 17th century: from latin territorium, from terra "land".

Examples:

1. The country claimed the territory as its own.
2. The company has expanded its territory into several new markets.
3. Birds of prey have a large territory they need to hunt and breed in.
4. The scientist was exploring new territory in his research.
5. She was determined to stake out her own territory in the workplace.