adjective
perpendicular
pur-puhn-DIHK-yuh-luh
adjective
1
Meeting another line or surface at a right angle (90 degrees).
"Make sure the fence post is perpendicular to the ground before you set the concrete."
"The two roads cross perpendicular to each other."
2
Standing straight up; exactly vertical.
"The cliff face rises almost perpendicular from the sea."
noun
1
A line or plane set at a right angle to another.
"Drop a perpendicular from the top of the triangle to find its height."
How to Use Perpendicular
Learner’s notesIn plain EnglishAt a right angle to something, or simply standing straight up.
Common pairings
perpendicular to the ground
perpendicular line
stand perpendicular
Word Forms
more perpendicular comparative, more Perpendicular comparative, perpendiculars plural, most perpendicular superlative, most Perpendicular superlative
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Etymology
From Latin perpendiculum, "a plumb line," the weighted string builders used to check for a true vertical.