In their dictionary, slavery is basically defined the same as in other countries. Slavery is the state of a person who has been viewed as property available to buy.
Slavery is when one person are kept by a "boss" to do work and hard labour for no reward. The slave has to do absolutely everything his boss requests from him.
Slavery is forcing someone to do work for no pay and usually under less-than-ideal circumstances. Slaves were usually treated very inhumanely and punished harshly for the smallest mistakes.