Definitions
1.NounA fortified defensive structure stationed with troops.
2.NounAny permanent army post.
3.NounAn outlying trading-station, as in British North America.
4.NounA structure improvised from furniture, bedding, etc., for playing games."The kids built a fort out of chairs and pillows."
5.VerbTo create a fort, fortifications, a strong point, or a redoubt.