ENGLISH
REFERENCE

perpendicular

adj.
B2 Upper Intermediate US //ˌpɝpənˈdɪkjəɫɝ// UK //pˌɜːpəndˈɪkjʊlɐ// per·pen·dic·u·lar Archaic Slang

adj. meeting or crossing at a right angle, like the letter T. You use this to describe two lines or walls that are perfectly square to each other.

adj. intersecting at or forming a right angle of ninety degrees. Often used in technical contexts to describe the relationship between two lines, planes, or surfaces.


SIMPLE

The vertical post must be perpendicular to the floor.

CONTEXTUAL

The architect designed the new wing to be perpendicular to the original structure to create a sheltered courtyard.

COMPLEX

In Euclidean geometry, two lines are considered perpendicular if they meet at a right angle, a principle fundamental to ensuring the structural integrity of load-bearing walls in modern construction.

Synonyms
Antonyms
Origin

Derived from Middle French perpendiculaire, from Old French perpendiculer, from Latin perpendiculum (“plumb line”).

Usage

Typically used as a predicative adjective after 'be' or 'remain', or as an attributive adjective before a noun.

Pitfall

The wall is perpendicular with the floor.The wall is perpendicular to the floor.The adjective 'perpendicular' takes the preposition 'to', not 'with'.

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