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epitheca

noun epi·theca \ "+ \
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Definition of epitheca

1 : an external calcareous layer investing the lower portion of the theca of many corals
2 : the outer or upper half or valve of the diatom frustule — compare hypotheca
—

epithecal

\"+\ or epithecate \"+\ adjective

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Origin and Etymology of epitheca

New Latin, from epi- + -theca

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