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epitheca

noun
epi·​theca | \"+\

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

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Other Words from epitheca

epithecal \"+ \ or epithecate \"+ \ adjective

History and Etymology for epitheca

New Latin, from epi- + -theca

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