Synonyms of perpendicular

perpendicular

adjective

ˌpər-pən-ˈdi-kyə-lər 

as in vertical

rising straight up

river rafters staring awestruck at the canyon's nearly perpendicular cliffs

Synonyms & Similar Words

• vertical
• standing
• erect
• upright
• plumb
• lifted
• raised
• upstanding
• upraised
• elevated
• stand-up
• upended
• freestanding
• stand-alone
• semierect

Antonyms & Near Antonyms

• flat
• recumbent
• diagonal
• prostrate
• supine
• hanging
• slant
• sagging
• slanted
• slanting
• slanty

Synonym Chooser

How does the adjective perpendicular differ from other similar words?

The words plumb and vertical are common synonyms of perpendicular. While all three words mean "being at right angles to a base line," 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

When is plumb a more appropriate choice than perpendicular?

While in some cases nearly identical to perpendicular, plumb stresses an exact verticality determined (as with a plumb line) by earth's gravity.

make sure that the wall is plumb

When is it sensible to use vertical instead of perpendicular?

While the synonyms vertical and perpendicular are close in meaning, vertical suggests a line or direction rising straight upward toward a zenith.

the side of the cliff is almost vertical

Example Sentences

Recent Examples of perpendicular

Turn the onion and make ½-inch slices perpendicular to the previous slices (crosswise on the onion). — Sarah Martens, Better Homes & Gardens, 1 Sep. 2026

Changing these printing conditions caused the molecules to align in one of two perpendicular directions. — Georgina Jedikovska, Interesting Engineering, 12 Aug. 2026

These reflect their echolocation calls away at an angle, rather than returning them, which can then cause bats to mistake this perpendicular echo pattern for open water or completely empty space. — Indrabati Lahiri, Forbes.com, 26 July 2026

Bend your knees and sit back so that your thighs are parallel to the floor, and your shins remain perpendicular. — Sarah Bence, Verywell Health, 8 June 2026