diagonal

[ dahy-ag-uh-nl, -ag-nl ]

/ daɪˈæg ə nl, -ˈæg nl /

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See synonyms for: diagonal / diagonals / diagonally on Thesaurus.com

adjective

Mathematics.

connecting two nonadjacent angles or vertices of a polygon or polyhedron, as a straight line.
extending from one edge of a solid figure to an opposite edge, as a plane.

having an oblique direction.

having oblique lines, ridges, markings, etc.

noun

a diagonal line or plane.

virgule.

a diagonal row, part, pattern, etc.

Manège. (of a horse at a trot) the foreleg and the hind leg, diagonally opposite, which move forward simultaneously.

diagonal cloth.

Mathematics. a set of entries in a square matrix running either from upper left to lower right (main diagonal, or principal diagonal ) or lower left to upper right (secondary diagonal ).

Chess. one of the oblique lines of squares on a chessboard: He advanced his bishop along the open diagonal.

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Origin of diagonal

First recorded in 1535–45; from Latin diagōnālis, from Greek diagṓn(ios) “from angle to angle” + Latin -ālis adjective suffix; see dia-, -gon, -al¹

OTHER WORDS FROM diagonal

di·ag·o·nal·ly, adverbnon·di·ag·o·nal, adjective, nounnon·di·ag·o·nal·ly, adverb

Words nearby diagonal

diagnosis, diagnostic, diagnosticate, diagnostician, diagnostics, diagonal, diagonal cloth, diagonalize, diagonal matrix, diagonal process, diagram

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use diagonal in a sentence

Basically, it gives a rough measurement of the diagonal line you could draw between the bottom left and the upper right corners.
How to pick the right TV to buy on Prime Day|Billy Cadden|June 21, 2021|Popular-Science
The probability that they would guess correctly was the fraction of the area that was on the “correct” side of the diagonal dividing line.
Are You Smarter Than A Fourth-Grader?|Zach Wissner-Gross (riddlercolumn@gmail.com)|May 14, 2021|FiveThirtyEight
The first night, they fell asleep on a diagonal sofa, happy and warm.
Texas is frozen and in crisis. A furniture store owner has emerged as a hero — again.|Cathy Free|February 18, 2021|Washington Post
Pro skier Drew Petersen teamed up with Salomon TV and Switchback Entertainment to demonstrate the diagonal and A-frame ski-carry techniques.
How to Carry Skis in the Backcountry|Outside Editors|February 3, 2021|Outside Online

In further simulations, they varied the number of diagonals as well as their spacing and thickness to find the lattice that could sustain the most compression.
The Curious Strength of a Sea Sponge’s Glass Skeleton|Elena Renken|January 11, 2021|Quanta Magazine
The young man weaves through clusters of bamboo and cuts a diagonal slash into a tree, positioning a hollow log at the end.
The Congo's Forgotten Colonial Getaway|Nina Strochlic|December 18, 2014|DAILY BEAST
But early on, his fictional people so often took the easy diagonal cut for betrayal.
Don Carpenter Was a Novelist Both Lacerating and Forgiving|Louis B. Jones|July 14, 2014|DAILY BEAST
A long, diagonal cross from Marcelo saw the ball reach Hulk, who brought it down to his feet from the top of his monumental chest.
World Cup 2014 Nail-Biter: Host Country Brazil Defeats Chile on Penalty Kicks|Tunku Varadarajan|June 28, 2014|DAILY BEAST
Others were paired with sportswear-inspired tops—think a tracksuit zip-up made glam with diagonal decorative panels.
Nicolas Ghesquière Presents His Debut Collection for Louis Vuitton|Liza Foreman|March 5, 2014|DAILY BEAST
I bought wine and I made a wine list and it was the first wine list of its kind: vertical, horizontal, and diagonal.
The Queen of the Cookbook|Sarah Whitman-Salkin|February 23, 2010|DAILY BEAST
The pillars are strengthened against lateral yielding by horizontal and diagonal bracing.
Encyclopaedia Britannica, 11th Edition, Volume 4, Part 3|Various
It was built at Chatham, from the design of Mr. Oliver Lang, of mahogany and on the diagonal principle.
Yachting Vol. 2|Various.
Construction: diagonal principle, Dantzic oak without, horizontal planking of Italian larch.
Yachting Vol. 2|Various.
At the left of the doorway, a bay window, also heavily curtained, is set into the diagonal wall.
Fifty Contemporary One-Act Plays|Various
At (a) the diagonal lines are used to distinguish the flat side of the neck from the round part of the bolt above it.
An Introduction to Machine Drawing and Design|David Allan Low

British Dictionary definitions for diagonal

diagonal

/ (daɪˈæɡənəl) /

adjective

maths connecting any two vertices that in a polygon are not adjacent and in a polyhedron are not in the same face

slanting; oblique

marked with slanting lines or patterns

noun

maths a diagonal line or plane

chess any oblique row of squares of the same colour

cloth marked or woven with slanting lines or patterns

something put, set, or drawn obliquely

another name for solidus (def. 1)

one front leg and the hind leg on the opposite side of a horse, which are on the ground together when the horse is trotting

Derived forms of diagonal

diagonally, adverb

Word Origin for diagonal

C16: from Latin diagōnālis, from Greek diagōnios, from dia- + gōnia angle

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for diagonal

diagonal

[ dī-ăg′ə-nəl ]

Adjective

Connecting two nonadjacent corners in a polygon or two nonadjacent corners in a polyhedron that do not lie in the same face.

Noun

A diagonal line segment.

diagonal

Origin of diagonal

OTHER WORDS FROM diagonal

Words nearby diagonal

Words related to diagonal

How to use diagonal in a sentence

British Dictionary definitions for diagonal

Derived forms of diagonal

Word Origin for diagonal

Scientific definitions for diagonal