1 of 2


per·​pen·​dic·​u·​lar ˌpər-pən-ˈdi-kyə-lər How to pronounce perpendicular (audio)
: standing at right angles to the plane of the horizon : exactly upright
: being at right angles to a given line or plane
: extremely steep : precipitous
often capitalized : of or relating to a medieval English Gothic style of architecture in which vertical lines predominate
: relating to, uniting, or consisting of individuals of dissimilar type or on different levels
perpendicularity noun
perpendicularly adverb


2 of 2


: a line at right angles to a line or plane (as of the horizon)
Choose the Right Synonym for perpendicular

vertical, perpendicular, plumb mean being at right angles to a base line.

vertical suggests a line or direction rising straight upward toward a zenith.

the side of the cliff is almost vertical

perpendicular may stress the straightness of a line making a right angle with any other line, not necessarily a horizontal one.

the parallel bars are perpendicular to the support posts

plumb stresses an exact verticality determined (as with a plumb line) by earth's gravity.

make sure that the wall is plumb

Examples of perpendicular in a Sentence

Adjective She lives on the street that is perpendicular to mine. river rafters staring awestruck at the canyon's nearly perpendicular cliffs
Recent Examples on the Web
In his earlier work, Schwartz identified two straight lines that are perpendicular to each other and also in the same plane, forming a T-pattern on every Möbius strip. Rachel Crowell, Scientific American, 12 Sep. 2023 In 2021, the Oceanside City Council approved spending up to $1 million on plans to find a source of supplemental sand, possibly from near-shore deposits in the ocean, and to build retention devices, such as rock groins extending perpendicular from the beach, to slow the loss of sand. Phil Diehl, San Diego Union-Tribune, 30 Aug. 2023 The bill did not directly expand the right to get to the shore in the first place, or what’s sometimes called perpendicular access. Brian Amaral,, 23 June 2023 If Earth’s tilt was perpendicular to its orbit around the sun, then the one hemisphere exposed to the sun would remain the same at all times of year. Caroline Delbert, Popular Mechanics, 23 Aug. 2023 Flight 1083 was cleared to land as well, but Flight 2133 continued to fly perpendicular to the airport and was still on a path toward the Medevac flight. Fernando Cervantes Jr., The Arizona Republic, 28 June 2023 Place your elbow on the floor, with your arm facing forward (perpendicular to your torso). Brett Williams, Men's Health, 18 May 2023 Once the driver gets to the destination safely, IQ can help parallel or perpendicular park with automatic steering, braking, and shifting. Umar Shakir, The Verge, 9 Aug. 2023 How to Do It: Widen your feet as much as possible with the shins still staying perpendicular to the floor when gripping the bar. Cori Ritchey, Men's Health, 7 Aug. 2023
Most people will place their rug perpendicular to their bed; the size will often come down to the dimensions of the room and how your furniture is laid out. Kelsey Mulvey, ELLE Decor, 13 July 2023 Aim to keep your forearm perpendicular to the floor, and keep your abs and shoulder blades tight. Men's Health, 7 July 2023 Rest right elbow on floor directly below right shoulder, with right forearm perpendicular to body and palm resting on the ground. Megan Falk, Women's Health, 28 June 2023 What to Look for in Amazon Watches for Men Case Size: The case size is determined by the width of the watch perpendicular to the strap, not including the crown—the knob on the side. Brad Lanphear, Men's Health, 20 June 2023 Keep your upper arm perpendicular to the ground throughout the movement. Brett Williams, Men's Health, 31 May 2023 How to Do It: Get down on the ground on your side, then place your elbow and forearm flat on the floor with your arm perpendicular to your torso facing out. Brett Williams, Men's Health, 27 May 2023 Groins are devices built of rock or concrete perpendicular to the beach, designed to catch and hold the longshore flow of sand. Phil Diehl, San Diego Union-Tribune, 12 Apr. 2023 The report cited video from a surveillance camera that was located on the ramp perpendicular to runway 18. Daniel McFadin, Arkansas Online, 18 Mar. 2023 See More

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

Word History



Middle English perpendiculer, from Middle French, from Latin perpendicularis, from perpendiculum plumb line, from per- + pendēre to hang — more at pendant

First Known Use


14th century, in the meaning defined at sense 1a


1551, in the meaning defined above

Time Traveler
The first known use of perpendicular was in the 14th century

Dictionary Entries Near perpendicular

Cite this Entry

“Perpendicular.” Dictionary, Merriam-Webster, Accessed 26 Sep. 2023.

Kids Definition


1 of 2 adjective
per·​pen·​dic·​u·​lar ˌpər-pən-ˈdik-yə-lər How to pronounce perpendicular (audio)
: exactly vertical or upright
: forming a right angle with each other or with a given line or plane
perpendicularly adverb


2 of 2 noun
: a perpendicular line


Middle English perpendiculer "exactly upright," from early French perpendiculer (same meaning), from Latin perpendicularis (same meaning), derived from per- "thoroughly" and pendēre "to hang" — related to depend, pendulum

More from Merriam-Webster on perpendicular

Last Updated: - Updated example sentences
Love words? Need even more definitions?

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