Wing Defence is correct. I too hated netball - most sports really. However I found this which will help us all understand the role of WD easily
The wing defence can go into the centre and defensive thirds, but NOT in the attacking third or the goal circle.
Their main job is to stop the ball reaching the opposition's goal circle.
They must intercept passes and feed them back to the attacking areas.
As well as getting the ball forward they have to mark the opposite wing attack.
The wing defence must be focused and good at controlling the ball.