tractrix

[trak-triks]

noun

Geometry.

plural

tractrices 

1. a curve whose tangents are all of equal length; the involute of a catenary.

Word History and Origins

Origin of tractrix¹

1720–30; < New Latin, equivalent to Latin trac-, variant stem of trahere to draw, pull + -trīx -trix

Example Sentences

The involute of the catenary is called the tractory, tractrix or antifriction curve; it has a cusp at the vertex of the catenary, and is asymptotic to the directrix.

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