These words refer to someone deprived of liberty, serving involuntarily or otherwise at the mercy of a master. Slave is the most common of these, the one with the widest range of uses. Specifically, it refers to someone who is owned by another and has no civil rights himself, particularly someone who serves involuntarily or is given no remuneration for his services. Most countries now prohibit the possession of slaves , a practice endemic throughout history, as in the case of conquerors who commonly made slaves of conquered peoples. Trade in slaves still persists in such places as Africa and the Middle East. In a more general sense, the word is often used today in informal speech to refer to anyone victimized by someone or something: a paternalistic company that not only expected its employees to work like slaves , but to be grateful for the chance; a slave to her own narrow egotism.

Bondman and bondmaid are now archaic except in a historical context; they refer to a man or woman bound to serve without wages. Unlike slave , these words could suggest a contractual agreement which might last for a certain term only and in which a degree of freedom was permitted to the bondman or bondmaid . On the literal level, thrall and vassal are also archaic, but, unlike the previous pair, both have surviving figurative uses. Thrall once indicated someone bound to personal service in a household; vassal , by contrast, indicated someone who was the master of his own affairs but pledged to serve his lord in was in exchange for protection within the lord’s domain. Thus, in its literal historical meaning, vassal contrasts sharply with these other words, since it could apply to people of any intermediate rank between the slave and the absolute master: barons who rebelled against being kept as vassals to their king. Because of legends in which the use of black magic could make one an unwilling thrall to an evil person, the word can suggest figurative enchantment, particularly a state of involuntary fascination: held in thrall by the exquisite music. Vassal , by comparison, is more often used to refer to any kind of forced allegiance or dependency: Iron Curtain countries that are no longer strict vassals of the Soviet Union.

Serf , like bondman , is now mostly archaic except in historical reference. Under feudalism, a serf was bound to an estate and could not leave it; whoever owned the land was perforce his master. Nevertheless the serf did have rights, unlike the slave , in that no one could drive him from the land or deny his right to be there. Serf can be used loosely for anyone in servile subjection, but this use can sound imprecise or far-fetched. In Latin America, peon once referred most specifically to someone held in involuntary servitude until he had paid a debt. Since this arrangement often proved permanent in practice, the word now refers to anyone so ridden by poverty as to be virtually a serf , or loosely, to any poorly paid labourer.