differential operator
n (Mathematics) any operator involving differentiation, such as the mathematical operator del ∇, used in vector analysis, where ∇ = i∂/∂x + j∂/∂y+ k∂/∂z, i, j, and k being unit vectors and ∂/∂x, ∂/∂y, and ∂/∂z the partial derivatives of a function in x, y, and z
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