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rhom·bus

(rŏmbəs)

n. pl. rhom·bus·esor rhom·bi (-bī)

An equilateral parallelogram, especially one having oblique angles. Also called rhomb.

[Late Latin, from Greek rhombos, bullroarer, lozenge-shaped flatfish, rhombus (a rhombus being so called in reference to lozenge-shaped wooden slat of a bullroarer), from rhembesthai, to roll about, go round and round; see wer-² in the Appendix of Indo-European roots.]

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rhombus

Indo-European & Semitic Roots Appendices

Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

Indo-European Roots

Semitic Roots

The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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