ellipsoid of revolution

9.0

A solid made by turning an oval around its middle line, like the Earth

noun
/ˌɛlɪˈspɔɪd əv rɪˈvʌlʊʃən/

Specialized

: elipsoide de revolución

The Earth is often modeled as an ellipsoid of revolution rather than a perfect sphere.

Examples

Many astronomical bodies have the shape of an ellipsoid of revolution due to their rotation.
By rotating an ellipse around its major axis, you create an ellipsoid of revolution.
An ellipsoid of revolution is a unique shape.
The ellipsoid of revolution is formed by rotating an ellipse.
Many astronomical bodies have the shape of an ellipsoid of revolution due to their rotation.
The Earth is often modeled as an ellipsoid of revolution rather than a perfect sphere.
By rotating an ellipse around its major axis, you create an ellipsoid of revolution.

Synonyms

spheroid

vsellipsoid of revolution

Specialized

1 7.3

A solid shape like a sphere but slightly flattened or stretched

refers to the surface produced when an ellipse is rotated around its principal axis

Surface Forms

ellipsoid of revolution singular

ellipsoids of revolution plural

Morphology

ellipsoid + of + revolution

The phrase literally describes an ellipsoid that is formed by a revolution (rotation), so a learner who knows 'ellipsoid' (a 3D shape with elliptical cross-sections) and 'revolution' (a complete rotation) can infer it denotes the shape produced by rotating an ellipse. The compositional pattern 'X of revolution' is a transparent, technical descriptive construction found across languages, so the meaning is predictable from the parts.

Etymology

The noun ellipsoid of revolution comes from a simple picture: take an ellipse, a stretched circle, and spin it around a straight line called the axis, and the 3D shape you make is an ellipsoid. So, it means the three-dimensional 'squashed' or 'stretched' ball you get by turning an ellipse, which is why we use it for planets like Earth.