Definition of diagonal
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>
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 knee
First Known Use: 1563
Other Mathematics and Statistics Terms
diagonal
Definition of diagonal
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
: 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

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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