Are there attacks that are neither melee nor ranged?

I was looking at the slow spell and realized its description states:

Regardless of the creature’s abilities or magic items, it can’t make more than one melee or ranged attack during its turn…

I was confused why it says “melee or ranged attack” instead of just “attack”, and thought perhaps there exists an attack that counts as neither melee nor ranged.

I realize it’s not exactly possible to prove a negative if there are no such attacks, but I still wonder:

Does such an attack exist?