paraboloid

American  

[puh-rab-uh-loid] / pəˈræb əˌlɔɪd /

noun

Geometry.

1. a surface that can be put into a position such that its sections parallel to at least one coordinate plane are parabolas.

---

paraboloid British  

/ pəˈræbəˌlɔɪd /

noun

1. a geometric surface whose sections parallel to two coordinate planes are parabolic and whose sections parallel to the third plane are either elliptical or hyperbolic. Equations x ²/ a ² ± y ²/ b ² = 2 cz

---

paraboloid Scientific  

/ pə-răb′ə-loid′ /

1. A surface having parabolic sections parallel to a single coordinate axis and elliptic sections perpendicular to that axis.

---

Other Word Forms

• paraboloidal adjective

Etymology

Origin of paraboloid

First recorded in 1650–60; parabol(a) + -oid

Example Sentences

He topped the whole thing off with a swooping, saddle-shaped roof — a hyperbolic paraboloid in design-speak — that gave it a distinct presence.

From New York Times • Jun. 13, 2023

Find the volume of the solid bounded by the paraboloid z = 2 − 9x2 − 9y2 and the plane z = 1.

From Textbooks • Mar. 30, 2016

The lower bound for r is zero, but the upper bound is sometimes the cone and the other times it is the paraboloid.

From Textbooks • Mar. 30, 2016

Figure 2.83 This quadric surface is called an elliptic paraboloid.

From Textbooks • Mar. 30, 2016

If it lies at the infinity, the plane at infinity is a tangent plane, and the surface is called a paraboloid.

From Encyclopaedia Britannica, 11th Edition, Volume 11, Slice 6 "Geodesy" to "Geometry" by Various