Hi, I need your help in my homework. My Instructor asked that question? Why there is not a work term in entropy balance equation?

I have researched about it and I found that,

entropy has not an exact physical meaning, however it is associated with disorder or randomness. In another point of view, entropy defines the energy which is unable to do work.
however I am not sure that these definitions are enough.

On the other hand, I think entropy is a mathematical derivation, which is done by a purpose of having a balance equation which does not involve a work term.
They have originated it from the one directional flow of heat (from high temperature to low). Is it true?

Thanks for your help

I am not in agreement with you
delta entropy = delta q(reversible)  / T
and q(reversible) = -w(reversible)
so work term is there