Formal and Legal:
* Slavery: This is the most direct and common synonym for involuntary servitude. It implies a complete lack of freedom and control over one's life.
* Forced labor: This term emphasizes the use of coercion and duress to make someone work against their will.
* Human trafficking: This term specifically refers to the recruitment, transportation, transfer, harboring, or receipt of people by means of threat, force, coercion, abduction, fraud, deception, abuse of power, or the taking advantage of a situation of vulnerability, for the purpose of exploitation.
* Peonage: This term refers to a system of debt bondage, where people are forced to work off a debt that they cannot realistically repay.
* Indentured servitude: This term refers to a system of labor where people agree to work for a specific period of time in exchange for passage, food, or other necessities. However, it is often considered involuntary servitude if the conditions of the agreement are unfair or if the person is unable to leave due to debt or other obligations.
Informal and More General:
* Bondage: This term emphasizes the feeling of being tied down or restricted.
* Captivity: This term emphasizes the feeling of being confined or imprisoned.
* Exploitation: This term emphasizes the unfair use of someone for personal gain.
* Oppression: This term emphasizes the feeling of being burdened or weighed down.
The best word to use will depend on the specific context and the message you are trying to convey.