Nonlinear and Unorthodox

Nonlinear adjective - Designating or involving an equation whose terms are not of the first degree.

Unorthodox and nonlinear are semantically related. In some cases you can use "Unorthodox" instead an adjective "Nonlinear".

Unorthodox adjective - Deviating from commonly accepted beliefs or practices.

Nonlinear and unorthodox are semantically related. You can use "Nonlinear" instead an adjective "Unorthodox".