Word for the Wise September 22, 2006 Broadcast Topic: The fourth estate
A listener asked how the press came to be known as the fourth estate, then followed up her initial question with this challenge: what are the other three estates? (来源：EnglishCN英语问答中心[e问e答])
Thanks to the excellent work of a high school history teacher, we have this one down cold. The three estates (or etats in French) date back to the Middle Ages, but most of us have learned about them in connection with the Ancien Regime that prevailed in France before the French Revolution.
The first estate refers to the clergy and to the monarch (the first of the traditional political estates, or etats). The second estate names the nobility, exclusive of the monarch. And the third estate, comprising about 98% of the French population before 1789, refers to the common people, or more specifically, to the bourgeoisie.
Fourth Estate has referred to "the public press" since at least as far back as the early 1800s. More generally, it has also been used to refer to any group other than the clergy, nobility, or commons that wields political power.