perpendicular

Definitions:

Hanging or extending in a right line from any point; at right angles to any plane or line; vertical.
- Etymological and pronouncing dictionary of the English language. By Stormonth, James, Phelp, P. H. Published 1874. (adjective) (adj.) (adjective)
An upright line; a line at right angles with another.
- The Winston Simplified Dictionary. By William Dodge Lewis, Edgar Arthur Singer. Published 1919. (noun) (n.) (noun)
Exactly upright; meeting at right angles.
- The Clarendon dictionary. By William Hand Browne, Samuel Stehman Haldeman. Published 1894. (adjective) (adj.) (adjective)
Perpendicularity.
- The Winston Simplified Dictionary. By William Dodge Lewis, Edgar Arthur Singer. Published 1919. (noun) (n.) (noun)
Extending in a straight line to the centre of the earth, or at right angles to the horizon; at right angles to a given line or surface.
- Nuttall's Standard dictionary of the English language. By Nuttall, P.Austin. Published 1914. (adjective) (adj.) (adjective)
A perpendicular line. See Perpend.
- Nuttall's Standard dictionary of the English language. By Nuttall, P.Austin. Published 1914. (noun) (n.) (noun)
At right angles to a line or surface; upright.
- The Winston Simplified Dictionary. By William Dodge Lewis, Edgar Arthur Singer. Published 1919. (adjective) (adj.) (adjective)
Perpendicularly.
- The Winston Simplified Dictionary. By William Dodge Lewis, Edgar Arthur Singer. Published 1919. (adverb) (adv.) (adverb)
A perpendicular line or plane.
- The american dictionary of the english language. By Daniel Lyons. Published 1899. (noun) (n.) (noun)
A line standing at right angles on another line.
- Etymological and pronouncing dictionary of the English language. By Stormonth, James, Phelp, P. H. Published 1874. (noun) (n.) (noun)
Exactly upright: extending in a straight line toward the centre of the earth: ( geom.) at right angles to a given line or surface.
- The american dictionary of the english language. By Daniel Lyons. Published 1899. (adjective) (adj.) (adjective)

Usage examples:

Fill it to the highest mark with milk fresh from the cow, and allow it to stand in a perpendicular position 24 hours.
- One Thousand Secrets of Wise and Rich Men Revealed by C. A. Bogardus
Let us suppose, for instance, that the star is situated near the pole of the ecliptic, then the telescope will be conveyed by the earth's motion in a direction perpendicular to its length.
- The Story of the Heavens by Robert Stawell Ball
Drewsteignton is a large village, and has a granite church, the tower of which is Decorated, and the nave Perpendicular
- Devon, Its Moorlands, Streams and Coasts by Rosalind Northcote