Definition of diagonal
1a : joining two vertices of a rectilinear figure that are nonadjacent or two vertices of a polyhedral figure that are not in the same faceb : passing through two nonadjacent edges of a polyhedron a diagonal plane
2a : inclined obliquely from a reference line (such as the vertical) wood with a diagonal grainb : having diagonal markings or parts a diagonal weave
Examples of diagonal in a sentence
The blanket is covered with diagonal stripes.
the diagonal design ran up the wall all the way from the lower left to the upper righthand corner
Origin and Etymology of diagonal
Latin diagonalis, from Greek diagōnios from angle to angle, from dia + gōnia angle; akin to Greek gony knee — more at ^{1}knee
First Known Use: 1563
Other Mathematics and Statistics Terms
diagonal
Definition of diagonal
1 : a diagonal straight line or plane
2a (1) : a diagonal direction (2) : a diagonal row, arrangement, or patternb : something oriented in diagonal position
3 : slash 4
on the diagonal
: in an oblique direction : diagonally
Examples of diagonal in a sentence
a design with strong diagonals
the ramp was set at a low diagonal to make it easier for physically challenged patrons
1571
First Known Use of diagonal
1571
Other Mathematics and Statistics Terms
DIAGONAL Defined for English Language Learners
Definition of diagonal for English Language Learners

of a straight line : joining two opposite corners of a shape (such as a square or rectangle) especially by crossing the center point of the shape

: not going straight across or up and down
diagonal
Definition of diagonal for English Language Learners

: a diagonal line, direction, or pattern
DIAGONAL Defined for Kids
Definition of diagonal for Students
1 : running from one corner to the opposite corner of a foursided shape (as a square) a diagonal line
2 : running in a slanting direction diagonal stripes
diagonally
\nəlē\ adverbDefinition of diagonal for Students
: a line, direction, or pattern that runs in a slanting direction
Learn More about diagonal

See words that rhyme with diagonal Thesaurus: All synonyms and antonyms for diagonal Spanish Central: Translation of diagonal Nglish: Translation of diagonal for Spanish speakers Britannica English: Translation of diagonal for Arabic speakers
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