ideology

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A set of doctrines or beliefs that are shared by the members of a social group or that form the basis of a political, economic, or other system.

from The Century Dictionary.

• noun The science of ideas or of mind; a name applied by the later disciples of the French philosopher Condillac to the history and evolution of human ideas, considered as so many successive forms or modes of certain original or transformed sensations; that system of mental philosophy which derives knowledge exclusively from sensation.

from the GNU version of the Collaborative International Dictionary of English.

• noun The science of ideas.
• noun (Metaph.) A theory of the origin of ideas which derives them exclusively from sensation.
• noun A set or system of theories and beliefs held by an individual or group, especially about sociopolitical goals and methods to attain them; in common usage, ideology is such a set of beliefs so strongly held by their adherents as to cause them to ignore evidence against such beliefs, and thus fall into error -- in this sense it is viewed as a negative trait; contrasted to pragmatism, and distinct from idealism.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun Doctrine, philosophy, body of beliefs or principles belonging to an individual or group.
• noun The study of the origin and nature of ideas.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun an orientation that characterizes the thinking of a group or nation
• noun imaginary or visionary theorization