In the jargon of Freemasonry, a lodge working the three fundamental Masonic degrees of Entered Apprentice, Fellow Craft, and Master Mason. Blue is the symbolic color of these three degrees, while other degrees have their own distinctive colors; the Royal Arch and its associated degrees, for example, have red for their color. See Freemasonry; Royal Arch.
SOURCE:
The Element Encyclopedia of Secret Societies : the ultimate a-z of ancient mysteries, lost civilizations and forgotten wisdom written by John Michael Greer – © John Michael Greer 2006