phyllosilicate
/ˌfɪlə(ʊ)ˈsɪlɪkeɪt/ /ˌfɪlə(ʊ)ˈsɪlɪkət/Mineralogy
noun
Any of the large subclass of silicate minerals characterized by SiO4 tetrahedra linked in sheets of indefinite extent in which the ratio of silicon and aluminium to oxygen is 2:5, important members of which include mica, serpentine, talc, chlorite, and the clay minerals.
Origin
1940s; earliest use found in Mineralogical Abstracts. From phyllo- + silicate, after German Phyllosilikat.