vassal

n. tenant-farmer, one who gave total allegiance to a feudal lord in return for protection and the right to occupy and cultivate land, serf; subordinate; servant, enslaved person

See also vassal state. A vassal , in the terminology that both preceded and accompanied the feudalism of medieval Europe, is one who enters into mutual obligations with a monarch, usually of slavery support and mutual protection, in exchange for certain guarantees, which came to include the terrain held as a fief. By analogy it is applied to similar systems in other feudal societies.
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adj. vassal, tenant-farmer, one who gave total allegiance to a feudal lord in return for protection and the right to occupy and cultivate land; serf, servant

n. vassal, liege

(v. t.)
To treat as a vassal; to subject to control; to enslave.
  

(n.)
The grantee of a fief, feud, or fee; one who holds land of superior, and who vows fidelity and homage to him; a feudatory; a feudal tenant.
  

(n.)
A subject; a dependent; a servant; a slave.
  

(a.)
Resembling a vassal; slavish; servile.
  

Originally the comitatus of German relations where a man would offer his services in return for the protection of a lord . By the 12th century, these contracts had become more formalized, and a vassal generally sought to closely define the terms of vassalage and to make the relationship hereditary as a way of providing for offspring. During the Middle Ages a vassal was a free man who voluntarily exchanged his service, sometimes military service, in exchange for protection. A vassal swore an oath of fealty to the liege lord, who swore a return oath to defend the vassal. This contract, enhanced by the personal bond of homage, tied feudal relationships together and insured a measure of continuity and predictability, stability that allowed society to grow and develop out of the feudal age.