Category:Infusorial

In`fu*so"ri*al, a. (Zoöl.)

Defn: Belonging to the Infusoria; composed of, or containing, Infusoria; as, infusorial earth. Infusorial earth (Geol.), a deposit of fine, usually white, siliceous material, composed mainly of the shells of the microscopic plants called diatoms. It is used in polishing powder, and in the manufacture of dynamite.