The phrase "litter type" refers to the specific kind or category of waste material, such as paper, plastic, or food, that is thrown away and can be found on the ground or in trash bins. Full definition
Give cats different choices of litter types and see which they choose. (iheartcats.com)
Have you recently changed litter types and / or brands? (cat-lovers-only.com)
If your cat resumes using the box in the same location with a different litter material, then you will know that he exhibits specific litter type preferences. (cathealth.com)