Definition of directrix in English:

directrix

Line breaks: dir|ec¦trix
Pronunciation: /dɪˈrɛktrɪks
 
, dʌɪ-/

noun (plural directrices /-trɪsiːz/)

Geometry
A fixed line used in describing a curve or surface.
More example sentences
  • In the following, the feet of perpendiculars dropped from points A, B, etc. on the parabola to the directrix will be denoted A ’, B ’, etc.
  • The focus and directrix of a hyperbola were considered by Pappus.
  • The directrix is used in the construction, which follows, mutatis mutandis, the same course as the above construction in the case of the ellipse.

Origin

early 18th century: from medieval Latin, literally 'directress', based on Latin dirigere 'to guide'.

Definition of directrix in:

Get more from Oxford Dictionaries

Subscribe to remove ads and access premium resources

Word of the day oleaginous
Pronunciation: ˌōlēˈajənəs
adjective
rich in, covered with, or producing oil; oily