Fourth Estate Meaning

(idiomatic) Journalism or journalists considered as a group; the press.

Example: 1603, John Florio, translating Michel de Montaigne, Folio Society 2006, vol. 1 p. 104:
  What is more barbarous than to see a nation […] where justice is lawfully denied him, that hath not wherewithall to pay for it; and that this merchandize hath so great credit, that in a politicall government there should be set up a fourth estate [tr. quatriesme estat] of Lawyers, breathsellers and pettifoggers […]