Rhomboids

Part of speech: noun

Definitions

1. A pair of quadrilateral shapes with opposite sides parallel and angles that are equal, often identified in geometry as a specific type of polygon
2. Two-dimensional figures characterized by opposite sides that are equal in length and slopes, commonly appearing in various geometric applications
3. A geometric term describing parallelograms that are not right-angled, exhibiting opposite sides that are both parallel and congruent

Etymology: "Rhomboids" is simply the plural of "rhomboid," so the history belongs to the singular. The base word comes from Greek "rhomboeides," built from "rhombos," a term for a spinning or rhythmically turning object, plus the suffix "-oeides," meaning "resembling" or "having the form of." A rhomboid is therefore a shape that looks like a rhombus, a figure once associated with a spinning top or a magic-drum-like object before geometers used it for a four-sided figure. The surprising part is that the rhombus and the rhomboid are close cousins in name but not in geometry. In Euclid's classification, a rhomboid is a parallelogram with adjacent sides of unequal length and non-right angles, while a rhombus has four equal sides. English took the word for this sense in the early modern period, so the rhomboid name carries a Greek shape-suffix that describes its resemblance to a rhombus rather than its exact identity.