alternate angle

noun

: one of a pair of angles with different vertices and on opposite sides of a transversal at its intersection with two other lines:
a
: one of a pair of angles inside the two intersected lines

called also alternate interior angle

b
: one of a pair of angles outside the two intersected lines

called also alternate exterior angle

Illustration of alternate angle

Illustration of alternate angle
  • a a′ b b′ alternate interior angles
  • c c′ d d′ alternate exterior angles

Example Sentences

Recent Examples on the Web Check out the alternate angle from one of our two AL.com videographers on the field for the game. Michael Casagrande | Mcasagrande@al.com, al, 5 Sep. 2021 Also, notice that the tops of the cutting teeth are ground at alternating angles, meaning one tooth angles to the left, the next to the right. Joseph Truini, Popular Mechanics, 24 July 2019

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'alternate angle.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1570, in the meaning defined above

Time Traveler
The first known use of alternate angle was in 1570

Dictionary Entries Near alternate angle

Cite this Entry

“Alternate angle.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/alternate%20angle. Accessed 4 Jun. 2023.

Kids Definition

alternate angle

noun
1
: one of a pair of angles on opposite sides of a line intersecting two other lines and between the two intersected lines

called also alternate interior angle

2
: one of a pair of angles on opposite sides of a line intersecting two other lines and outside the two intersected lines

called also alternate exterior angle

Last Updated: - Definition revised
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!