adj. 1. (Math.) Not depictable graphically as a straight line; not changing by a constant amount for each unit of time, distance, or other independent variable. Opposite of linear. [ WordNet 1.5 +PJC ]
2. (Math.) Containing variables of greater than the first degree; -- of an equation. Opposite of linear. [ PJC ]
3. (Physics) Represented by equations containing variables of greater than the first degree; -- of physical processes or relationships. Opposite of linear. [ PJC ]