princely state

Noun

 * 1) a political state, in the widest sense, which is ruled as or like a principality in the generic sense, regardless of the ruler's actual title and rank.
 * 2)  a vassal state under the indirect rule of the British Raj, which is governed by an Indian ruler

Usage notes

 * Generally used for the feudal domains of native potentates maintained under indirect rule in European colonies, mainly British India where there were hundreds of them, while Western princes are said to reign over 'principalities'.