rhombus (n.) Look up rhombus at Dictionary.com
1560s, from Late Latin rhombus, from Greek rhombos "rhombus, rhomb, lozenge; spinning top, maghic wheel used by sorcerers; a spinning motion," from rhembesthai "to spin, whirl," from PIE *wrembh-, from *werbh- "to turn, twist, bend" (source also of Old English weorpan "to throw away"), from root *wer- (3) "to turn, bend" (see versus).