What do people mean by 'Void'?

[Minimasher]

I've seen a lot of people trading villagers talk about their voids???
I recently picked up a villager from someone and they said "don't worry my void is clear".
I said thank you even though I had no idea what they meant.
Could someone please explain to me what a void is?
Thank you

 

[Aardbei]

Hello !

The void is the "place" where villagers who have moved out from your town are. If you play with someone who has a free plot, one of these villagers can buy it even if the person you've been playing with never saw this vilager in your town before.

And because of the "I've moved out" glitch it's better, at the moment, to play with people who have a clear void

 

[spCrossing]

From what I remember in New Leaf, "voiding" means a state where a villager moves out of your town but hasn't picked a specific destination on where to go.
I.E. the villager moving out isn't picked up by another person visiting your town with an empty space in their town for the villager to move into.
That void villager will basically go to a random town on your switch friend's list if they have an open plot for a villager to move in.

Hope that explains what voiding means. ovob