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

Also consider corner clearances and make sure door and drawer hardware will clear the items perpendicular to them. —Madeline Buiano, Martha Stewart, 19 Feb. 2026

There’s a dusty cloud surrounding the central, contracting star, and that cloud is strongly suspected to be disk-like, with outflows and gaps in the dust in the two directions perpendicular to the disk. —Big Think, 11 Feb. 2026

Vonn tried to twist and regain her balance in mid-air but landed awkwardly with her skis perpendicular to the fall line, ensuring a brutal fall. —Andrew Dampf, Denver Post, 8 Feb. 2026

If the lever is perpendicular to the gas line, the gas valve is shut off. —Timothy Dale, The Spruce, 28 Jan. 2026