Definition:Lituus

Definition

The lituus is the locus of the equation expressed in polar coordinates as:

$r^2 = \dfrac {a^2} \theta$

Also see

• Results about the lituus can be found here.

Linguistic Note

The word lituus literally means trumpet in Latin.

An ancient Roman-Etruscan trumpet differs in shape from the contemporary instrument.

It is also a fancy staff or wand used in certain religious rituals.

Its shape echoes that of the lituus.

Its plural form is litui.

Sources

• 1989: Ephraim J. Borowski and Jonathan M. Borwein: Dictionary of Mathematics ... (previous) ... (next): lituus
• 1998: David Nelson: The Penguin Dictionary of Mathematics (2nd ed.) ... (previous) ... (next): lituus
• 1998: David Nelson: The Penguin Dictionary of Mathematics (2nd ed.) ... (previous) ... (next): spiral
• 2008: David Nelson: The Penguin Dictionary of Mathematics (4th ed.) ... (previous) ... (next): lituus
• 2008: David Nelson: The Penguin Dictionary of Mathematics (4th ed.) ... (previous) ... (next): spiral