Zirconoid n. : A double eight-sided pyramid, a form common with tetragonal crystals; -- so called because this form often occurs in crystals of zircon.

Example:


Taxonomy
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Defination from the web:
zirconoid. Definition from Wiktionary, a free dictionary. Jump to: navigation, search. Part or all of this page has been imported from the 1913 edition of Webster's Dictionary, which is now free of copyright and hence in the public domain. ...