perpendicular

American  

[pur-puhn-dik-yuh-ler] / ˌpɜr pənˈdɪk jə lər /

adjective

1. vertical; straight up and down; upright.

   Synonyms:

   standing

2. Geometry. meeting a given line or surface at right angles.

3. maintaining a standing or upright position; standing up.

4. having a sharp pitch or slope; steep.

5. (initial capital letter) noting or pertaining to the last style of English Gothic architecture, prevailing from the late 14th through the early 16th century and characterized by the use of predominantly vertical tracery, an overall linear, shallow effect, and fine intricate stonework.

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noun

perpendiculars plural

1. a perpendicular line or plane.

2. an instrument for indicating the vertical line from any point.

3. an upright position.

4. a sharply pitched or precipitously steep mountain face.

5. moral virtue or uprightness; rectitude.

6. Nautical. either of two lines perpendicular to the keel line, base line, or designed water line of a vessel.

perpendicular British  

/ ˌpɜːpənˌdɪkjʊˈlærɪtɪ, ˌpɜːpənˈdɪkjʊlə /

adjective

1. Also: normal.  at right angles to a horizontal plane

2. denoting, relating to, or having the style of Gothic architecture used in England during the 14th and 15th centuries, characterized by tracery having vertical lines, a four-centred arch, and fan vaulting

3. upright; vertical

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noun

1. geometry a line or plane perpendicular to another

2. any instrument used for indicating the vertical line through a given point

3. mountaineering a nearly vertical face

perpendicular Scientific  

/ pûr′pən-dĭk′yə-lər /

1. Intersecting at or forming a right angle or right angles.

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1. A line or plane that is perpendicular to a given line or plane.

Synonym Usage

See upright.

Other Word Forms

Derived Forms

• nonperpendicularity
  noun
• perpendicularity
  noun
• perpendicularness
  noun
• nonperpendicular
  adjective
• unperpendicular
  adjective
• nonperpendicularly
  adverb
• perpendicularly
  adverb
• unperpendicularly
  adverb

Inflected Forms

Nouns

• perpendiculars
  plural

Etymology

Origin of perpendicular

First recorded in 1350–1400; from Latin perpendiculāris “vertical,” equivalent to perpendicul(um) “plumb line” ( see perpend ², -i-, -cule ²) + -āris -ar ¹; replacing Middle English perpendiculer(e) (adjective and adverb), from Old French perpendiculiere

Explanation

Two lines that form a T are perpendicular to each other. They meet at a right angle. A person who is standing is perpendicular to the earth. Use perpendicular to describe lines, angles, and direction. In geometry a perpendicular angle is 90 degrees, a perfect L. On a compass, East and North are perpendicular to each other. The term can be used more generally to describe any steep angle. You might talk about a ski slope that is nearly perpendicular but that's impossible since gravity would make you fall off a 90-degree angle. But if it's close enough, no one's really measuring.

Example Sentences

Perpendicular lines are lines in the same plane that form a right angle.

From Textbooks • Apr. 22, 2020

Darly’s 1775 portrait, Corporal Perpendicular, is the earliest work in the exhibition and will be exhibited alongside art by Audrey Niffenegger, Posy Simmonds, Sarah Lightman and Kate Brown.

From The Guardian • Jan. 29, 2016

He suggested I check out one of the completed trails to see the crew’s finished work, so I headed across the island to the Perpendicular Trail on the shores of Long Pond.

From New York Times • Aug. 8, 2014

I emphasized this contrarian aspect of Dyson's personality in my 1993 profile of him for Scientific American, titled "Perpendicular to the Mainstream".

From Scientific American • Jan. 7, 2011

So did its people, and this majestic Perpendicular church, built of flint and stone, is an abiding monument of their wealth and of their piety.

From Through East Anglia in a Motor Car by Vincent, J. E. (James Edmund)

Related Words

• erect
• on end
• plumb