From BiblePortal Wikipedia

Webster's Dictionary [1]

(1): ( n.) In France, before the Revolution, the assembly of the three orders of the kingdom, namely, the clergy, the nobility, and the third estate, or commonalty.

(2): ( n.) In the Netherlands, the legislative body, composed of two chambers.

The Nuttall Encyclopedia [2]

Name given to an assembly of the representatives of the three estates of nobles, clergy, and bourgeoisie, or the Tiers État as it was called, in France prior to the Revolution of 1789, and which was first convoked in 1302 by Philip IV.; they dealt chiefly with taxation, and had no legislative power; they were convoked by Louis XIII. in 1614, and dismissed for looking into finance, and not convoked again till the last time in 1789, for the history of which see Carlyle'S "French Revolution."