When you decamp, you leave or depart very suddenly, or in secret. If your rent in Brooklyn keeps going up, you may decide to decamp to New Jersey.
Use the verb decamp when people scram — especially when they relocate a household or a business to a new location. You'll probably be disappointed when your favorite pizza place decamps to another neighborhood, or if your best friend's family decamps to Canada. The word was originally a military term, literally meaning "leave camp," from the French décamper, from des-, "apart or away," and camp, "open space for military exercises."