# Partial derivative

From AMS Glossary

## partial derivative

The ordinary derivative of a function of two or more variables with respect to one of the variables, the others being considered constants.

If the variables are

*x*and*y*, the partial derivatives of*F*(*x*,*y*) are written ∂*f*/∂*x*and ∂*f*/∂*y*, or*D*_{x}*f*and*D*_{y}*f*, or*f*_{x}and*f*_{y}. The partial derivative of a variable with respect to time is known as the local derivative.