Meaning of DIAGONAL in English

DIAGONAL

I. dī-ˈa-gə-n ə l, -ˈag-nəl adjective

Etymology: Latin diagonalis, from Greek diagōnios from angle to angle, from dia- + gōnia angle; akin to Greek gony knee — more at knee

Date: 1563

1.

a. : joining two vertices of a rectilinear figure that are nonadjacent or two vertices of a polyhedral figure that are not in the same face

b. : passing through two nonadjacent edges of a polyhedron

a diagonal plane

2.

a. : inclined obliquely from a reference line (as the vertical)

wood with a diagonal grain

b. : having diagonal markings or parts

a diagonal weave

II. noun

Date: 1571

1. : a diagonal straight line or plane

2.

a.

(1) : a diagonal direction

(2) : a diagonal row, arrangement, or pattern

b. : something oriented in diagonal position

3. : slash 4

- on the diagonal

Merriam-Webster's Collegiate English vocabulary.      Энциклопедический словарь английского языка Merriam Webster.