vassal
/ˈvæsl; `væsl/ n
1 (in the Middle Ages) man promising to fight for and be loyal to a king or lord in return for the right to hold land （中世纪的）封臣, 家臣（为国君或领主效忠可受封土地者）.
2 (fig 比喻) person or nation dependent on another 附庸; 下属; 属国
[attrib 作定语]
vassal states, kingdoms, etc 附庸国、 王国等.