What Does (\frac{\partial z}{\partial x})y Indicate?

[brandy]

($\frac{\partial z}{\partial x}$)_y

the small y, what does it mean.
the context this is used in is F(x,y,z) where each variable is a function of the other 2 variables.

 

[D H]

It means that y is to be deemed a constant while taking the partial of z with respect to x.