1. (Science: chemical) A fine white claylike mineral, soft, and light enough when in dry masses to float in water. It is a hydrous silicate of magnesia, and is obtained chiefly in asia minor. It is manufacturd into tobacco pipes, cigar holders, etc. Also called sepiolite.
Origin: G, lit, sea foam; meer sea _ schaum foam; but it perh. Is a corruption of the Tartaric name myrsen. Cf. Mere a lake, and Scum.