diagonal

1 of 2

adjective

di·​ag·​o·​nal dī-ˈa-gə-nᵊl 

-ˈag-nəl

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 (such as the vertical)

wood with a diagonal grain

b

: having diagonal markings or parts

a diagonal weave

diagonal

2 of 2

noun

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 sense 4

Phrases

on the diagonal

: in an oblique direction : diagonally

Synonyms

Adjective

• cant
• canted
• graded
• inclined
• leaning
• listing
• oblique
• pitched
• raked
• slant
• slanted
• slantwise
• sloped
• sloping
• tilted
• tilting

Noun

• cant
• grade
• gradient
• inclination
• incline
• lean
• pitch
• rake
• slant
• slope
• upgrade

Examples of diagonal in a Sentence

Adjective

The blanket is covered with diagonal stripes.

the diagonal design ran up the wall all the way from the lower left to the upper right-hand corner

Noun

a design with strong diagonals

the ramp was set at a low diagonal to make it easier for physically challenged patrons

Recent Examples on the Web

Adjective

Add Cheese Using a sharp knife, score both sides of each cheese round in a diamond pattern by making shallow diagonal cuts 1 inch apart. —Elizabeth Fogarty, Better Homes & Gardens, 4 Dec. 2024

With a maximum image size of 120 inches on the diagonal from a projector that fits in the palm of your hand, this is a great choice for movie nights, presentations, and more, especially at a 34% price drop. —K. Thor Jensen, PCMAG, 1 Dec. 2024

Noun

This pattern was repeated in the session, this time with Evans playing a diagonal to Malacia. —Mark Carey, The Athletic, 23 Nov. 2024

So, too, does the drama of his composition, which pits rows of people against the diagonals of the rocky outcroppings all around—a Giotto-esque flourish, to be sure, but one filtered through Duccio’s personal tastes. —Alex Greenberger, ARTnews.com, 11 Oct. 2024

Word History

Etymology

Adjective

Latin diagonalis, from Greek diagōnios from angle to angle, from dia- + gōnia angle; akin to Greek gony knee — more at knee entry 1

First Known Use

Adjective

1563, in the meaning defined at sense 1a

Noun

1571, in the meaning defined at sense 1

Phrases Containing diagonal

• diagonal matrix
• on a diagonal
• on the diagonal
• principal diagonal

Kids Definition

diagonal

1 of 2 adjective

di·​ag·​o·​nal dī-ˈag-ən-ᵊl 

-ˈag-nəl

1

: joining two opposite corners of a four-sided figure

2

: running in a slanting direction

diagonally

-ən-ᵊl-ē

-nə-lē

adverb

diagonal

2 of 2 noun

1

: a diagonal line or direction

2

: a diagonal row, arrangement, or pattern

3

: slash entry 2 sense 2