latus rectum

noun, plural la·ter·a rec·ta [ley-ter-uh rek-tuh] /ˈleɪ tər ə ˈrɛk tə/. Geometry.

1. the chord perpendicular to the principal axis and passing through a focus of an ellipse, parabola, or hyperbola.

noun plural latera recta (ˈlætərə ˈrɛktə)

1. geometry a chord that passes through the focus of a conic and is perpendicular to the major axis