Incipient Spinner.
You wrote: used to emphasise the difference between a wing drop which one just picks up (rudder not aileron)
"Picking up a wing with rudder" is a hoary old myth from war time days, yet amazingly is still taught by some flying schools as God's Own Truth. You appear to have fallen for that myth.
If a one wing drops at point of stall, the correct technique is to prevent further yaw caused by the downgoing wing with appropriate rudder while at the same time unstalling the wings with forward stick and levelling the wings with aileron.