Word Study
graptolite
CIDE DICTIONARY
graptolite, n. [NL, Graptolithus, from Gr. is engraved, written (gra`fein to write) + stone.].
One of numerous species of slender and delicate fossils, of the genus Graptolites and allied genera, found in the Silurian rocks. They belong to an extinct group (Graptolithina ) supposed to be hydroids. [1913 Webster]
OXFORD DICTIONARY
graptolite, n. an extinct marine invertebrate animal found as a fossil in lower Palaeozoic rocks.
Etymology
Gk graptos marked with letters + -LITE
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