Definition of "perpendicular" []

• Mathematics Intersecting at or forming right angles. (adjective)
• Being at right angles to the horizontal; vertical. See Synonyms at vertical. (adjective)
• Of or relating to a style of English Gothic architecture of the 14th and 15th centuries, characterized by emphasis of the vertical element. (adjective)
• In a perpendicular position. (adverb)
• Mathematics A line or plane perpendicular to a given line or plane. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "In fixing a barometer for observation, it is indispensable that it be hung in a perpendicular position, seeing that it is the _perpendicular distance_ between the surface of the mercury in the cistern and the top of the column which is the true height of the barometer."
• "Shouldn't she be resting instead of dashing to-and-fro, drying the raindrops that land in perpendicular plop-plop!"
• "The only corkscrew she had was a solid wooden-handled one with the screw sticking out perpendicular from the center (like a letter “T”)."