directrix

English

Etymology

Latin directrix; equivalent to direct +‎ -trix

Noun

In this picture of an ellipse, a parabola, and an hyperbola, the black line is their shared directrix.

directrix (plural directrixes or directrices)

1. A female who directs; a directress.
2. (geometry) A line used to define a curve or surface; especially a line, the distance from which a point on a conic has a constant ratio to that from the focus.

Derived terms

• conic section directrix
• graph directrix
• ruled surface directrix

 

Translations

a line used to define a curve or surface

• Dutch: richtlijn (nl) m or f
• Finnish: johtosuora
• French: directrice (fr) f
• Polish: kierownica (pl) f
• Spanish: directriz (es) f
• Tamil: இயக்குவரை (ta) f (iyakkuvarai)

a female who directs — see directress

Anagrams

• creditrix