plural noun
Bac·​il·​lar·​i·​o·​phy·​ce·​ae | \ -əˈfīsēˌē, -əˈfis-\

Definition of Bacillariophyceae

: a class of yellow-green algae (division Chrysophyta) comprising the diatoms

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First Known Use of Bacillariophyceae

1931, in the meaning defined above

History and Etymology for Bacillariophyceae

New Latin, from Bacillaria + -o- + -phyceae

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The first known use of Bacillariophyceae was in 1931

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