1. A usually religious movement or point of view characterized by a return to fundamental principles, by rigid adherence to those principles, and often by intolerance of other views and opposition to secularism.
2. 1. often Fundamentalism An organized, militant Evangelical movement originating in the United States in the late 19th and early 20th century in opposition to Protestant Liberalism and secularism, insisting on the inerrancy of Scripture.
   2. Adherence to the theology of this movement.

The American Heritage® Dictionary of the English Language, Fourth Edition Copyright © 2007, 2000 by Houghton Mifflin Company. Updated in 2009. Published by Houghton Mifflin Company. All rights reserved.