An outpost is a camp or station that's somewhat isolated. A military outpost acts as a guard or defense against an enemy's attack on the larger military force.
Whenever a small group of people sets up a camp at a distance from the main, larger organization (whether it's military or not), you can call their settlement an outpost. Explorers in the early days of the US set up outposts throughout the West, and many countries establish outposts near their borders with hostile neighbors — encampments for keeping an eye on them. The first written use of outpost2020欧洲杯时间 is usually ascribed to George Washington.