There are multiple definitions - click on the translation that matches your context.

Besitz

Substantiv

full

possession

noun

Definitions of possession

English

if you possess property then you have control over it (but do not necessarily own it)

It would be illegal for the owners to take back possession of the house without a court order.

English

if you have something in your possession then that you are carrying with you or physically holding it

Four people were arrested on suspicion of possession with intent to supply controlled drugs, and a fifth person was arrested on suspicion of possession.