Roget's 21st Century Thesaurus, Third Edition Copyright © 2013 by the Philip Lief Group.

WORD ORIGIN

"unwillingness to endure a differing opinion," 1765, from Latin intolerantia "impatience, unendurableness, insufferableness, insolence," from intolerantem (see intolerant). Especially of religious matters through mid-19c. Now-obsolete intolerancy was used in same sense from 1620s.