If it is also the use of "move" or "movement" then, if an effect "moves" an opponent some distance, that is forced movement, would it be affected by Difficult Terrain? (I can't think of an example that fits this so it's a hypothetical for now.)
Oh snap! It is but it's also a new Harengon hole. There was a thread where we were discussing whether creatures have movement outside of their turn. Dissonant Whispers depends on creatures having off-turn movement, no? Is it worth bring up over there?
I think it's this one Ready Action to intercept enemy? (I mentioned that spell as an example of movement off-turn, indeed)
But regarding Dissonant Whispers and movement we have also Dissonant Whispers question