"Soiled litter" refers to litter that has become dirty or contaminated, usually by waste or dirt.
Sentences with «soiled litter»
Most cats prefer sand or soil litter as they would use in the wild. (tampabayvets.net)
Leave a small amount of soiled litter in the tray to build up a scent association for the kitten. (messybeast.com)
Leaving a pad or paper with a bit of urine on it under the new fresh one or leaving a few bits of soiled litter in the fresh litter in his box is plenty! (thehousebreakingbible.com)