Nonlinear

A function that is not linear. Most things in nature are nonlinear. This means that in a very real way, the whole is at least different from the sum of the parts. See also holism.
Found on http://mitpress.mit.edu/books/FLAOH/cbnhtml/glossary.html

nonlinear

[adj] - math
Found on http://www.webdictionary.co.uk/definition.php?query=nonlinear

nonlinear

adjective designating or involving an equation whose terms are not of the first degree
Found on http://wordnetweb.princeton.edu/perl/webwn?s=nonlinear
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