What does paraboloid mean?
A paraboloid is a three-dimensional curved form associated with the geometry of a parabola. In its strict mathematical sense, it is the surface created when a parabola is rotated around its axis; the term may also denote a solid bounded by such a surface or a physical device shaped like one. Paraboloids are important in engineering because their geometry can focus or concentrate waves. Parabolic dishes used for satellite communication, radio telescopes, microphones, and reflecting telescopes rely on this property, with reflected or received signals tending to converge toward a focal point. The family includes convex forms, commonly called elliptic paraboloids, and saddle-shaped forms known as hyperbolic paraboloids. Although the word belongs primarily to technical vocabulary, it identifies a distinctive geometric idea: it is to a parabola what a sphere is to a circle, with the crucial added dimension supplied by rotation.
nounA paraboloid is a curved surface generated by rotating a parabola around its axis. The term can also refer to a solid or practical device with this shape, especially a curved reflector used in optics, acoustics, or antenna engineering.
- A curved geometric surface generated by rotating a parabola about its axis.
- A solid or physical object whose surface has this form, such as a bowl-shaped reflector or antenna dish.
"The engineer designed a shallow paraboloid to focus radio waves onto the receiver."
"The satellite signal was directed by a large paraboloid toward the ground station."
"The surface of the dish forms a paraboloid, allowing incoming waves to converge at its focus."
The plural is used when referring to multiple geometric surfaces, solids, or devices of this form.
"Several paraboloids were installed to collect and focus radio signals."
Rotate a parabola around its axis and it becomes a paraboloid—the same transformation that turns a circle into a sphere.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does paraboloid come from?
The English mathematical noun was formed from the stem parabola- together with the suffix -oid, meaning “like” or “resembling.” The stem ultimately comes through Latin from Greek parabolē, a term associated with placing something beside another for comparison and later with the mathematical curve. The combined term was established within mathematical terminology for a surface generated by revolving a parabola. Related English words such as parabola, parabolic, and parabolically preserve the same Greek and Latin root.
Related word forms
How paraboloid is actually used
The word is formal and specialist, chiefly used in mathematics, surveying, optics, acoustics, and antenna engineering. Outside technical contexts, people may describe a practical example by its function or familiar shape rather than by its geometric name.
Easily confused with paraboloid
A parabola is a two-dimensional curve, whereas a paraboloid is a three-dimensional surface or solid produced by rotating such a curve around its axis.