What is the meaning of D(conj) in the Symbolic Toolbox?

When I calculate the derivate of a special function such as a complex conjugate I receive a D(conj) as part of my answer. I would like to know what this variable means.

Answer 1

[MathWorks Support Team]

The Symbolic Math Toolbox uses D(conj) as a shorthand to specify the derivative with respect to a natural logarithm. This notation may be used when the statement can not be simplified further.

For instance, the output statement

 D(conj)(a)

is equivalent to

 diff(conj(a))