A more thorough explanation:

Vis clandestina (pronounced vis klan-des-ti-nuh) is a Latin term that refers to the use of force in secret, especially during the night.

During the Middle Ages, many lords and knights would use vis clandestina to attack their enemies' castles or steal their livestock. They would wait until nightfall and then sneak into the enemy's territory to carry out their mission.

In modern times, some criminal organizations use vis clandestina to carry out illegal activities, such as smuggling drugs or weapons. They operate in secret and try to avoid detection by law enforcement.

The examples illustrate how vis clandestina refers to the use of force in secret, especially during the night. In both cases, the perpetrators try to avoid detection by operating in secret and using stealth to carry out their mission. This term is often associated with illegal or unethical activities, as it implies a lack of transparency and accountability.