berylloid

noun

ber·​yl·​loid

ˈber-ə-ˌlȯid

plural -s

: a form consisting of a double 12-sided pyramid : the dihexagonal dipyramid

Word History

Etymology

International Scientific Vocabulary beryll- (probably from Latin beryllus) + -oid; from the frequent occurrence of beryl crystals in this form

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