vermiculite[vər mik′yə līt′]
any of a number of very soft, monoclinic, hydrous silicate minerals resulting usually from alterations of mica and occurring in tiny, leafy scales that expand greatly when heated: used for insulation, water adsorption, etc.
Origin of vermiculite; from Classical Latin vermiculus, diminutive of vermis, worm + -ite
Any of a group of micaceous hydrated silicate minerals related to the chlorites and used in heat-expanded form as insulation and as a planting medium.
Origin of vermiculiteLatin vermiculus, diminutive of vermis, worm; see vermicular + –ite1.
(countable and uncountable, plural vermiculites)