Word Study
vermiculite
CIDE DICTIONARY
vermiculite, n. [L. vermiculus, dim. of vermis worm.].
A group of minerals having, a micaceous structure. They are hydrous silicates, derived generally from the alteration of some kind of mica. So called because the scales, when heated, open out into wormlike forms. [1913 Webster]
OXFORD DICTIONARY
vermiculite, n. a hydrous silicate mineral usu. resulting from alteration of mica, and expandable into sponge by heating, used as an insulation material.
Etymology
as VERMICULATE + -ITE(1)
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