That’s still just a filter. A filter is something that separates and divides a mixed group into specific categories. So a reverse filter would be the opposite of that. Something that takes separate groups and mixes them together.

Strainers and sieves are filters. A filter is a filter. A reverse filter is still a filter. Direction doesn’t make a difference because direction is subjective.

I like tmro. It rolls off the tongue nicely

They were less confrontational and more likely to accept direction