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[pur-puh n-dik-yuh-ler] /ˌpɜr pənˈdɪk yə lər/
vertical; straight up and down; upright.
Geometry. meeting a given line or surface at right angles.
maintaining a standing or upright position; standing up.
having a sharp pitch or slope; steep.
(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.
a perpendicular line or plane.
an instrument for indicating the vertical line from any point.
an upright position.
a sharply pitched or precipitously steep mountain face.
moral virtue or uprightness; rectitude.
Nautical. either of two lines perpendicular to the keel line, base line, or designed water line of a vessel.
Origin of perpendicular
1350-1400; < Latin perpendiculāris vertical, equivalent to perpendicul(um) plumb line (see perpend2, -i-, -cule2) + -āris -ar1; replacing Middle English perpendiculer(e) (adj. and adv.) < Old French perpendiculiere
Related forms
perpendicularity, perpendicularness, noun
perpendicularly, adverb
nonperpendicular, adjective, noun
nonperpendicularly, adverb
nonperpendicularity, noun
unperpendicular, adjective
unperpendicularly, adverb
1. standing. See upright. Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
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Examples from the web for perpendicular
  • Repeat perpendicular cuts at the other end of the center cut.
  • Draw a second line—running "east" to "west"—perpendicular to the first.
  • Let me call the direction perpendicular to the ground, the y-direction.
  • In no time, I noticed a woman in the seat perpendicular to ours staring at me.
  • When the upper-level winds are perpendicular to the surface front they keep the front moving.
  • Though storms make them stronger, they really only need a steady, fresh breeze blowing perpendicular to the shore to stir them up.
  • The people move up and down, but the wave moves perpendicular to that.
  • From these facts, it seems that the condors require perpendicular cliffs.
  • The fans sat, six to a side, at long tables perpendicular to the stage.
  • This tripod allows for its legs to open perpendicular to the vertical shaft of your tripod.
British Dictionary definitions for perpendicular


Also normal. at right angles to a horizontal plane
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
upright; vertical
(geometry) a line or plane perpendicular to another
any instrument used for indicating the vertical line through a given point
(mountaineering) a nearly vertical face
Derived Forms
perpendicularity (ˌpɜːpənˌdɪkjʊˈlærɪtɪ) noun
perpendicularly, adverb
Word Origin
C14: from Latin perpendiculāris, from perpendiculum a plumb line, from per- through + pendēre to hang
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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Word Origin and History for perpendicular

late 15c., from adverb (late 14c.), from Old French perpendiculer, from Latin perpendicularis "vertical, as a plumb line," from perpendiculum "plumb line," from perpendere "balance carefully," from per- "thoroughly" (see per) + pendere "to weigh, to hang" (see pendant). As a noun from 1570s. Related: Perpendicularly; perpendicularity.

Online Etymology Dictionary, © 2010 Douglas Harper
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perpendicular in Science
Adjective  Intersecting at or forming a right angle or right angles.

Noun  A line or plane that is perpendicular to a given line or plane.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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