Definition:Cone (Geometry)/Double Napped Cone

Definition

A double napped cone is a cone where the lines joining the apex to the circumference of the base extend indefinitely in either dimension:

Nappe

Each of the halves of a double napped cone is a nappe.

Also known as

A double napped cone is also known as a double cone.

Some sources hyphenate: double-napped cone.

Also see

• Definition:Bicone

• Results about double napped cones can be found here.

Sources

• 1998: David Nelson: The Penguin Dictionary of Mathematics (2nd ed.) ... (previous) ... (next): conic (conic section)
• 2008: David Nelson: The Penguin Dictionary of Mathematics (4th ed.) ... (previous) ... (next): conic (conic section)

• Weisstein, Eric W. "Double Cone." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/DoubleCone.html