# Partial derivative

In mathematics, partial derivative, or "partial differential", signified by curl d or "curly d" derivative symbol (∂), is an infinitesimal change in a function consisting of two or more variables when one of the variable changes and the others remain constant. [1] In the function z = f(x,y), for instance, the partial derivative of z with respect to x, while y remains unchanged is:

$\Bigg( \frac{\partial z}{\partial x} \Bigg)_{y} \,$

History
The notation and logic of the partial differential or partial derivative was introduced in 1786 by French mathematician Adrien-Marie Legendre and later adopted by German mathematician Carl Jacobi in 1841.

References
1. Daintith, John. (2005). Oxford Dictionary of Science. Oxford University Press.