Added 10 October 2026 mosaicism noun Categories: Describing WordsRare Words noun ! Definition from WordNet 3.1, Princeton University. More about mosaicism at Wordnik → Where our words come from → The condition in which an organism has two or more cell populations that differ in genetic makeup. Related Words: confinedmozaicismmosaicpolymitosismixoploidymultiploidmixoploidmultimutationpolymorphismmultigenicitymeromicticitymonosomaty Back to today's word