The definition of perpendicular is something that is at right angles to something else.(adjective)
An example of something that is perpendicular is a light post that is standing upright next to a street.
See perpendicular in Webster's New World College Dictionary
Origin: ME perpendiculer < OFr < L perpendicularis < perpendiculum, plumb line < perpendere, to weigh carefully < per-, intens. + pendere, to hang: see pendant
See perpendicular in American Heritage Dictionary 4
Origin: Middle English perpendiculer
Origin: , from Old French
Origin: , from Latin perpendiculāris
Origin: , from perpendiculum, plumb line
Origin: , from perpendere, to weigh carefully
Origin: : per-, per-
Origin: + pendere, to weigh; see (s)pen- in Indo-European roots.
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