The term Fourth Estate refers to the press, both in its explicit capacity of advocacy and in its implicit ability to frame political issues. The term goes back at least to Thomas Carlyle in the first half of the 19th century.
None of our political writers ... takes notice of any more than three estates, namely, Kings, Lords, and Commons ... passing by in silence that very large and powerful body which form the fourth estate in this community ... The Mob.3
by bclark86 August 07, 2008