Syntax for gradient

Hello everyone

I am building a model that has gradient of dependent variables in the source term. The syntax for any dependent variable 'u' is 'ux'. But, my source term has terms like gradient(u*v). ( u & v are dependent variables). I tried using pd(u*v), but the results are incorrect. Partial derivative gives only the scalar value. I need gradient for the direction. Is there any syntax for this - gradient(u*v) ?