1. Not in a straight line.
a. Occurring as a result of an operation that is not linear.
b. Containing a variable with an exponent other than one. Used of an equation.
a. Of or relating to a system of equations whose effects are not proportional to their causes. Such a set of equations can be chaotic.
b. Of or relating to a device whose behavior is described by a set of nonlinear equations and whose output is not proportional to its input.
c. Of or relating to the output of such a device.
non·lin′e·ari·ty (-ârĭ-tē) n.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2019 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.