A fine, compact, usually white claylike mineral of hydrous magnesium silicate, H4Mg2Si3O10, found in the Mediterranean area and used in fashioning tobacco pipes and as a building stone. Also called sepiolite.
A tobacco pipe with a bowl made of this mineral.
[German : Meer, sea (from Middle High German mer, from Old High German mari; see mori- in Indo-European roots) + Schaum, foam (from Middle High German schūm, from Old High German scūm; see (s)keu- in Indo-European roots).]