Word Study
infusorial
CIDE DICTIONARY
infusorial, a.
Belonging to the Infusoria; composed of, or containing, Infusoria; as, infusorial earth. [1913 Webster]
Infusorial earth (Geol.), a deposit of fine, usually white, siliceous material, composed mainly of the shells of the microscopic plants called diatoms ; also called diatomaceous earth , kieselguhr , and diatomite . It is used in polishing powder, and in the manufacture of dynamite.
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