magnesium silicate

noun Chemistry.

a white powder, 3MgSiO3⋅5H2O, with variable hydration, insoluble in water or alcohol, used as a rubber filler, a bleaching agent, an odor absorbent, and in the manufacture of paints and resins.
any silicate containing magnesium, as enstatite, talc, or magnesium trisilicate. Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019