rhombus

American  

[rom-buhs] / ˈrɒm bəs /

noun

rhombuses, plural rhombi plural

1. an oblique-angled equilateral parallelogram; any equilateral parallelogram except a square.

2. an equilateral parallelogram, including the square as a special case.

3. a rhombohedron.

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rhombus British  

/ ˈrɒmbəs /

noun

1. Also called: rhomb.  an oblique-angled parallelogram having four equal sides Compare square

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rhombus Scientific  

/ rŏm′bəs /

rhombuses plural

1. A parallelogram with four equal sides; an equilateral parallelogram.

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Other Word Forms

Noun Inflected Forms

• rhombi
  plural
• rhombuses
  plural

Etymology

Origin of rhombus

First recorded in 1560–70; from Latin, from Greek rhómbos “anything that may be spun around,” derivative of rhémbein “to revolve”

Compare meaning

How does rhombus compare to similar and commonly confused words? Explore the most common comparisons:

• rhombus vs. parallelogram

Explanation

A rhombus is a parallelogram with four equal sides and opposite equal angles. A rhombus can be a square, or if it has two acute angles and two obtuse angles, it takes the shape of a diamond. The rhombus gets its name from the Greek rhómbos, which means "a spinning top." This word describes the shape of a "bullroarer," an object that was tied to a cord and spun around, making a great noise. It was used to taunt bulls into action during bull-fighting events. This rhombus-shaped object has been documented as being used for religious rites and games all over the ancient world. Nowadays, we prefer to study the rhombus in geometry.

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